MACK T310 Service Manual

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TRANSMISSION

T310

SERVICE MANUAL

APRIL 2003

(NEW ISSUE)

10-126

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TRANSMISSION

T310

SERVICE MANUAL

APRIL 2003 (NEW ISSUE)

10-126

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ATTENTION

The information in this manual is not all inclusive and cannot take into account all unique situations. Note that some illustrations are typical and may not reflect the exact arrangement of every component installed on a specific chassis.

The information, specifications, and illustrations in this publication are based on information that was current at the time of publication.

No part of this publication may be reproduced, stored in a retrieval system, or be transmitted in any form by any means including (but not limited to) electronic, mechanical, photocopying, recording, or otherwise without prior written permission of Mack Trucks, Inc.

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TABLE OF CONTENTS

iii

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TABLE OF CONTENTS

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

SAFETY INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Advisory Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Service Procedures and Tool Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

EXPLANATION OF NUMERICAL CODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

CONVERSION CHART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

VISUAL IDENTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

TRANSMISSION IDENTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Unit Identification Stamping Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

DESCRIPTION AND OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

DESCRIPTION AND OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

T310 Transmissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Gear Ratios and Shift Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

T310 Shifting Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Power Flow Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

COMPONENT LOCATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

COMPONENT LOCATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

TROUBLESHOOTING CHARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

TRANSMISSION MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Checking Oil Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Changing Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Change Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Draining Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Oil Fill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Magnetic Oil Filter Plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Air Breather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

REPAIR INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

TRANSMISSION DISASSEMBLY PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

TRANSMISSION COMPONENT DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Main Case Shift Cover Disassembly [323] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Two-Position Range Shift Cylinder Disassembly [324] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Range Shift Valve [323] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Main Drive Pinion Disassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Front Mainshaft Disassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Rear Mainshaft and Synchronizer Disassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Synchronizer Disassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Rear Mainshaft Bearing Cover Disassembly [321] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Compound Main Drive Gear Disassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Front Countershaft Front Bearing Cover Disassembly [321] . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Front Countershaft Disassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Front Countershaft Rear Bearing Cover Disassembly [321] . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Rear Countershaft Disassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

Rear Countershaft Bearing Cover Disassembly [321] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Reverse Idler Gear Disassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

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INSPECTION OF PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Inspection and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94

Bearings [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Gears [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Shifter Forks, Sliding Clutches and Shift Rails [323] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Oil Seals [321] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

General Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

General Reassembly Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96

TRANSMISSION COMPONENT REASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Reverse Idler Gear Reassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Rear Countershaft Bearing Cover Reassembly [321] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Rear Countershaft Reassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Front Countershaft Rear Bearing Cover Reassembly [321] . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Front Countershaft Reassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

Front Countershaft Front Bearing Cover Reassembly [321] . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Compound Main Drive Gear Reassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

Rear Mainshaft Bearing Cover Reassembly [321] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Synchronizer Reassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Rear Mainshaft Reassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

Front Mainshaft Reassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

Main Drive Pinion Reassembly [322] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

Range Shift Valve [323] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

Two-Position Range Shift Cylinder Reassembly [324] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Main Case Shift Cover Reassembly [323] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

TRANSMISSION REASSEMBLY PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

TABLE OF CONTENTS

SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

Torque Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

Gear Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172

Fits and Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174

General Tolerances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

Transmission Specifications and Capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176

SCHEMATIC & ROUTING DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

SCHEMATIC DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178

Air Piping Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178

Air Control Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

SPECIAL TOOLS & EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

SPECIAL TOOLS AND EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

Special Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

DISASSEMBLED VIEWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

DISASSEMBLED VIEWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184

INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

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NOTES

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INTRODUCTION

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INTRODUCTION

SAFETY INFORMATION

Advisory Labels

Cautionary signal words (Danger-Warning-Caution) may appear in various locations throughout this manual. Information accented by one of these signal words must be observed to minimize the risk of personal injury to service personnel, or the possibility of improper service methods which may damage the vehicle or cause it to be unsafe. Additional Notes and Service Hints are used to emphasize areas of procedural importance and provide suggestions for ease of repair. The following definitions indicate the use of these advisory labels as they appear throughout the manual:

Activities associated with Danger indicate that death or serious personal injury may result from failing to heed the advisory. Serious personal injury may be equated to career-ending injury.

Activities associated with Warning indicate that personal injury may result from failing to heed the advisory. In this case, personal injury is not equated to career-ending injury, but results in possible change in quality of life.

Activities associated with Caution indicate that product damage may result from failing to heed the advisory. Caution is not used for personal injury.

A procedure, practice, or condition that is essential to emphasize.

A helpful suggestion that will make it quicker and/or easier to perform a procedure, while possibly reducing service cost.

Page 2

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Service Procedures and Tool Usage

Anyone using a service procedure or tool not recommended in this manual must first satisfy himself thoroughly that neither his safety nor vehicle safety will be jeopardized by the service method he selects. Individuals deviating in any manner from the instructions provided assume all risks of consequential personal injury or damage to equipment involved.

Also note that particular service procedures may require the use of a special tool(s) designed for a specific purpose. These special tools must be used in the manner described, whenever specified in the instructions.

1. Before starting a vehicle, always be seated in the driver’s seat, place the transmission in neutral, be sure that parking brakes are set, and disengage the clutch.

INTRODUCTION

2. Before working on a vehicle, place the transmission in neutral, set the parking brakes, and block the wheels.

3. Before towing the vehicle, place the transmission in neutral and lift the rear wheels off the ground, or disconnect the driveline to avoid damage to the transmission during towing.

Engine-driven components such as Power Take-Off (PTO) units, fans and fan belts, driveshafts and other related rotating assemblies, can be very dangerous. Do not work on or service engine-driven components unless the engine is shut down. Always keep body parts and loose clothing out of range of these powerful components to prevent serious personal injury. Be aware of PTO engagement or nonengagement status. Always disengage the PTO when not in use.

REMEMBER,

SAFETY. . .IS NO ACCIDENT!

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INTRODUCTION

Mack Trucks, Inc. cannot anticipate every possible occurrence that may involve a potential hazard. Accidents can be avoided by recognizing potentially hazardous situations and taking necessary precautions. Performing service procedures correctly is critical to technician safety and safe, reliable vehicle operation.

The following list of general shop safety practices can help technicians avoid potentially hazardous situations and reduce the risk of personal injury. DO NOT perform any services, maintenance procedures or lubrications until this manual has been read and understood.

r Perform all service work on a flat, level

surface. Block wheels to prevent vehicle from rolling.

r DO NOT wear loose-fitting or torn clothing.

Remove any jewelry before servicing vehicle.

r ALWAYS wear safety glasses and protective

shoes. Avoid injury by being aware of sharp corners and jagged edges.

r Use hoists or jacks to lift or move heavy

objects.

r NEVER run engine indoors unless exhaust

fumes are adequately vented to the outside.

r Be aware of hot surfaces. Allow engine to

cool sufficiently before performing any service or tests in the vicinity of the engine.

r Keep work area clean and orderly. Clean up

any spilled oil, grease, fuel, hydraulic fluid, etc.

r Only use tools that are in good condition,

and always use accurately calibrated torque wrenches to tighten all fasteners to specified torques. In instances where procedures require the use of special tools which are designed for a specific purpose, use only in the manner described in the instructions.

r Do not store natural gas powered vehicles

indoors for an extended period of time (overnight) without first removing the fuel.

r Never smoke around a natural gas powered

vehicle.

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INTRODUCTION

EXPLANATION OF NUMERICAL CODE

The organization of MACK service manuals has been upgraded to standardize manual content according to a reference system based on component identification. The reference system helps link the information contained in this publication with related information included in other MACK service-warranty publications, such as associated service bulletins, warranty manuals, and MACK Service Labor Time Standards.

The system is based on a numerical code first digit of which identifies the general component grouping as listed here:

GROUP 000 — GENERAL DATA

GROUP 100 — CHASSIS

GROUP 200 — ENGINE

GROUP 300 — CLUTCH, TRANSMISSION, TRANSFER CASE AND PTO

, the

GROUP 400 — STEERING, AXLES, WHEELS AND TIRES, DRIVELINE

GROUP 500 — BRAKES, AUXILIARY SYSTEMS

GROUP 600 — CAB, TRUCK BODY

GROUP 700 — ELECTRICAL

The second two digits of the 3-digit code are used to identify the system, assembly or subassembly, as appropriate, within each of the groupings. The codes applicable to this publication are shown at the beginning of each procedure, as necessary, to guide you to specific component information.

Additionally, a two-character alpha code [GA] CASE, MAIN) may be shown with each operation. This alpha code, in combination with the three-digit Group number, identifies the specific assembly, subassembly or part, and directly relates to the first five positions of the operation code listed in the MACK Service Labor Time Standards.

(i.e.,

Example of Numerical Code

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INTRODUCTION

CONVERSION CHART

Conversion Units Multiply By:

Length Calculations

Inches (in) to Millimeters (mm) 25.40

Inches (in) to Centimeters (cm) 2.540

Feet (ft) to Centimeters (cm) 30.48

Feet (ft) to Meters (m) 0.3048

Yards (yd) to Centimeters (cm) 91.44

Yards (yd) to Meters (m) 0.9144

Miles to Kilometers (km) 1.609

Millimeters (mm) to Inches (in) 0.03937

Centimeters (cm) to Inches (in) 0.3937

Centimeters (cm) to Feet (ft) 0.0328

Centimeters (cm) to Yards (yd) 0.0109

Meters (m) to Feet (ft) 3.281

Meters (m) to Yards (yd) 1.094

Kilometers (km) to Miles 0.6214

Area Calculations

Square Inches (sq-in) to Square Millimeters (sq-mm) 645.2

Square Inches (sq-in) to Square Centimeters (sq-cm) 6.452

Square Feet (sq-ft) to Square Centimeters (sq-cm) 929.0

Square Feet (sq-ft) to Square Meters (sq-m) 0.0929

Square Yards (sq-yd) to Square Meters (sq-m) 0.8361

Square Miles (sq-miles) to Square Kilometers (sq-km) 2.590

Square Millimeters (sq-mm) to Square Inches (sq-in) 0.00155

Square Centimeters (sq-cm) to Square Inches (sq-in) 0.155

Square Centimeters (sq-cm) to Square Feet (sq-ft) 0.001076

Square Meters (sq-m) to Square Feet (sq-ft) 10.76

Square Meters (sq-m) to Square Yards (sq-yd) 1.196

Square Kilometers (sq-km) to Square Miles (sq-miles) 0.3861

Volume Calculations

Cubic Inches (cu-in) to Cubic Centimeters (cu-cm) 16.387

Cubic Inches (cu-in) to Liters (L) 0.01639

Quarts (qt) to Liters (L) 0.9464

Gallons (gal) to Liters (L) 3.7854

Cubic Yards (cu-yd) to Cubic Meters (cu-m) 0.7646

Cubic Centimeters (cu-cm) to Cubic Inches (cu-in) 0.06102

Liters (L) to Cubic Inches (cu-in) 61.024

Liters (L) to Quarts (qt) 1.0567

Liters (L) to Gallons (gal) 0.2642

Cubic Meters (cu-m) to Cubic Yards (cu-yd) 1.308

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Weight Calculations

Ounces (oz) to Grams (g) 28.5714

Pounds (lb) to Kilograms (kg) 0.4536

Pounds (lb) to Short Tons (US tons) 0.0005

Pounds (lb) to Metric Tons (t) 0.00045

Short Tons (US tons) to Pounds (lb) 2000

Short Tons (US tons) to Kilograms (kg) 907.18486

Short Tons (US tons) to Metric Tons (t) 0.90718

Grams (g) to Ounces (oz) 0.035

Kilograms (kg) to Pounds (lb) 2.205

Kilograms (kg) to Short Tons (US tons) 0.001102

Kilograms (kg) to Metric Tons (t) 0.001

Metric Tons (t) to Pounds (lb) 2205

Metric Tons (t) to Short Tons (US tons) 1.1023

Metric Tons (t) to Kilograms (kg) 1000

Force Calculations

Ounces Force (ozf) to Newtons (N) 0.2780

Pounds Force (lbf) to Newtons (N) 4.448

Pounds Force (lbf) to Kilograms Force (kgf) 0.456

Kilograms Force (kgf) to Pounds Force (lbf) 2.2046

Kilograms Force (kgf) to Newtons (N) 9.807

Newtons (N) to Kilograms Force (kgf) 0.10196

Newtons (N) to Ounces Force (ozf) 3.597

Newtons (N) to Pounds Force (lbf) 0.2248

Torque Calculations

Pound Inches (lb-in) to Newton Meters (N·m) 0.11298

Pound Feet (lb-ft) to Newton Meters (N·m) 1.3558

Pound Feet (lb-ft) to Kilograms Force per Meter (kgfm) 0.13825

Newton Meters (N·m) to Pound Inches (lb-in) 8.851

Newton Meters (N·m) to Pound Feet (lb-ft) 0.7376

Newton Meters (N·m) to Kilograms Force per Meter (kgfm) 0.10197

Kilograms Force per Meter (kgfm) to Pound Feet (lb-ft) 7.233

Kilograms Force per Meter (kgfm) to Newton Meters (N·m) 9.807

Radiator Specific Heat Dissipation Calculations

British Thermal Unit per Hour (BTU/hr) to Kilowatt per Degree Celsius (kW/°C) 0.000293

Kilowatt per Degree Celsius (kW/°C) to British Thermal Unit per Hour (BTU/hr) 3414.43

Temperature Calculations

Degrees Fahrenheit (°F) to Degrees Celsius (°C) (°F32) 0.556

Degrees Celsius (°C) to Degrees Fahrenheit (°F) (1.8 x °C) + 32

INTRODUCTION

Conversion Units Multiply By:

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INTRODUCTION

Conversion Units Multiply By:

Pressure Calculations

Atmospheres (atm) to Bars (bar) 1.01325

Atmospheres (atm) to Kilopascals (kPa) 101.325

Bars (bar) to Atmospheres (atm) 0.98692

Bars (bar) to Kilopascals (kPa) 100

Bar (bar) to Pounds per Square Inch (psi) 14.5037

Inches of Mercury (in Hg) to Kilopascals (kPa) 3.377

Inches of Water (in H

Pounds per Square Inch (psi) to Kilopascals (kPa) 6.895

Pounds per Square Inch (psi) to Bar (bar) 0.06895

Kilopascals (kPa) to Atmospheres (atm) 0.00987

Kilopascals (kPa) to Inches of Mercury (in Hg) 0.29612

Kilopascals (kPa) to Inches of Water (in H

Kilopascals (kPa) to Pounds per Square Inch (psi) 0.145

Power Calculations

Horsepower (hp) to Kilowatts (kW) 0.74627

Kilowatts (kW) to Horsepower (hp) 1.34

Fuel Performance Calculations

Miles per Gallon (mile/gal) to Kilometers per Liter (km/L) 0.4251

Kilometers per Liter (km/L) to Miles per Gallon (mile/gal) 2.352

Velocity Calculations

Miles per Hour (mile/hr) to Kilometers per Hour (km/hr) 1.609

Kilometers per Hour (km/hr) to Miles per Hour (mile/hr) 0.6214

Volume Flow Calculations

Cubic Feet per Minute (cu-ft/min) to Liters per Minute (L/min) 28.32

Liters per Minute (L/min) to Cubic Feet per Minute (cu-ft/min) 0.03531

O) to Kilopascals (kPa) 0.2491

O) 4.01445

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VISUAL IDENTIFICATION

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VISUAL IDENTIFICATION

TRANSMISSION IDENTIFICATION

Figure 1 — Location of Identification Stamping on Left Side of Main Case

Unit Identification Stamping Location

The following model code information is stamped on the left side of the transmission, toward the rear of the main case. Refer to Figure 1.

1. Unit Symbol Identification T = transmission 3 = 300 series 10 = useable forward speeds

2. Transmission Serial No.

3. Transmission Assembly (Part) No. * = digits may vary

4. Specific variant of the base assembly number (variant to item No. 3)

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VISUAL IDENTIFICATION

Figure 2 — Cutaway View of T310 Transmission

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NOTES

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DESCRIPTION AND OPERATION

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DESCRIPTION AND OPERATION

T310 Transmissions

DESCRIPTION

The T310 transmission is a member of a new family of MACK transmissions designated as MAXITORQUE These transmissions are the next evolution of the durable triple-countershaft transmission. New features and product enhancements have been engineered into these transmissions to provide a wide range of advantages which include the following:

r New and revised gear ratios for greater

overall range and versatility

r Lower “LOs” in forward and reverse for

superior site maneuvering

r Improved shift quality through the use of a

new sliding clutch with a fine-pitch tooth design versus the coarse-pitch tooth design of previous transmissions

r Enhanced durability

r Weight reduction versus the previous series

transmissions

The T310 transmissions are triple-countershaft units. They consist of a compact main box which houses five non-synchronized forward-speed gear sets plus a reverse gear set. The rear case of the T310 transmission is also a triplecountershaft unit. The rear case consists of Lorange and Hi-range gear sets which are air controlled by an air shift selector located on the main shift lever.

ES (T300) Series transmissions.

All gears are of the spur-type design and are in constant mesh with mating gears. All shifting is done by forks and sliding clutches. The shift rails and forks are integral with the shift cover for the main case.

A single gear shift lever is used to shift through a standard “H” pattern. An air shift range selector, mounted on the gear shift lever, is also used for shifting the T310. The range selector directs air pressure to the compound air shift cylinder. Operating the selector causes a shift between Hi range or Lo range in the compound.

The T310 has 10 forward speeds and two reverse speeds. Each of the five forward speeds in the main case is used once with the compound in Lo range (first, second, third, fourth and fifth), and once more with the compound in Hi range (sixth, seventh, eighth, ninth and tenth). Reverse may be used in either Lo range or Hi range. See Figure 7.

The compound range shift is accomplished using a plate-type synchronizer, shifted by a range shift cylinder and a shift fork.

The six countershafts, three in the main case and three in the rear case, are equally spaced around the mainshafts. This design distributes the load equally among the countershafts, thus keeping normal deflection and gear tooth loading to a minimum.

The main case and the bell housing are a onepiece casting, made from aluminum and heattreated for strength.

The main case also has 6- and 8-bolt openings that allow for the addition of Power Take-Off (PTO) units. PTO operation is off the (53 tooth) countershaft fifth (10th) speed gear.

The bearings are housed in cast-iron bearing retainers (covers). Tapered roller bearings are used at each end of all transmission countershafts.

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Figure 3 — Equal Torque Distribution

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DESCRIPTION AND OPERATION

Lubrication

SPLASH LUBRICATION

All parts inside the transmission are lubricated by a splash-and-gravity system. To minimize churning, only the lower countershaft dips into the lubrication oil. As the gears on that countershaft spin, a constant spray of oil is directed to all internal parts of the transmission. The oil cools as it circulates over the aluminum case. Troughs and passages, cast into the inside of the case, capture and direct oil to the bearings.

Figure 4 — Splash Lubrication

TRANSMISSION CASE OIL COOLER LINE PLUGS

Figure 5 — Transmission Case Oil Cooler Line Plugs

1. Outlet Plastic Cap 2. Suction Tube Plug

MAGNETIC OIL FILTER

A magnetic oil filter assembly is built into the right side of the main case. It consists of a magnetic plug which removes ferrous metallic particles from the passing oil. After passing the magnetic plug, the oil is channelled upward to an outlet, where it returns (by gravity) down into the transmission case sump. The magnetic plug is removable from the outside of the transmission, without the necessity of draining the oil since this plug is above the oil level. The drain plug at the bottom of the case is also magnetic.

An integral oil cooler pump system has been developed for MACK T300 series transmissions. The oil cooler is optional for engine ratings under 400 hp and chassis ratings under 80,000 GVW. The oil cooler system is required when the engine rating is equal to or exceeds 400 hp, or the chassis rating is greater than 80,000 GVW.

On T310 transmissions that are not built with oil cooler pump systems, the tube line openings are plugged or capped. The main suction tube area contains a metal plug and the outlet fitting area receives a plastic cap.

Figure 6 — Plug Locations

1. Magnetic Filter Plug

2. Oil Temperature Sensor

3. Oil Drain Plug

4. Oil Fill and Level Plug

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DESCRIPTION AND OPERATION

Gear Ratios and Shift Pattern

Figure 7 — T310 Gear Ratios and Shift Pattern

Gear Position (Main Box) Lo-Range Ratios Hi-Range Ratios

1/6 13.81 2.67

2/7 10.05 1.94

3/8 7.18 1.39

4/9 5.17 1.00

5/10 3.75 0.73

R/R 14.73 2.75

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DESCRIPTION AND OPERATION

T310 Shifting Instructions

Make sure air pressure is at least 100 psi and unit is warmed before making range shifts. Always start in Lo range. This also applies to dynamometer testing. When the truck is stationary, do NOT shift into Hi range and then start moving the truck. Otherwise, damage to the synchronizer may result. To avoid transmission damage, do not change range while in reverse.

The T310 unit is a range-shifted transmission which has 10 forward “highway” speeds. This transmission features a Lo and Hi auxiliary compound section controlled by an air shift range selector located on the shift lever. The compound section is equipped with a synchronizer to facilitate Lo-/Hi-range shifting.

The Lo range provides five low ratios. Never attempt to move the vehicle from a stopped position in any gear higher than fifth speed gear. Depending on load, grade, or road conditions, it may be necessary to start in first, second, third or fourth speed gears. In Hi range there are five forward gears that can be shifted in the standard manner. Always remember, however, to double clutch whether moving up or down through these gears. Reverse gear can be used in Lo range or Hi range.

UPSHIFTING (NORMAL HIGHWAY)

DOWNSHIFTING (NORMAL HIGHWAY)

Shift from 10th speed gear down through the Hi range (9-8-7-6), double clutching through each gear. While still in sixth speed gear, flip the air shift range selector down to Lo range (preselect). Then move the shift lever through neutral to fifth speed gear. As the shift lever passes through neutral, the transmission is placed into Lo range. Then, shift down to fourth, third, second and first speed gears, double clutching between all gears.

r Always start in Lo range according to shift

marker plate instructions. Never start in a gear higher than fifth speed gear, even when dynamometer testing.

r When the truck is stationary, do not shift into

Hi range and then start moving the truck. Damage to the synchronizer can result.

r Be careful not to overspeed the engine

during downshifting. Damage to powertrain components may result.

r To avoid transmission damage, do not

change range while moving in reverse gear.

Power Flow Diagrams

The following illustrations show power flow through the T310 transmission in each gear range.

With the shift lever in neutral, flip the air shift range selector down to Lo range. Then shift the transmission into first gear. Shift up to second, third, fourth and fifth speed gears, double clutching between the gears. When maximum engine RPM has been reached in fifth gear, flip the air shift range selector up to Hi range (preselect). Then move the shift lever through neutral to sixth gear. As the shift lever passes through neutral, the transmission is placed into Hi range. Continue following the normal sequence (7-8-9-10), being sure to double clutch from one gear to the next.

Figure 8 — First Speed

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DESCRIPTION AND OPERATION

Figure 9 — Second Speed

Figure 12 — Fifth Speed

Figure 11 — Fourth Speed

Figure 10 — Third Speed

Figure 13 — Sixth Speed

Figure 14 — Seventh Speed

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DESCRIPTION AND OPERATION

Figure 15 — Eighth Speed

Figure 18 — Reverse Speed (Lo)

Figure 16 — Ninth Speed

Figure 19 — Reverse Speed (Hi)

Figure 17 — Tenth Speed

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NOTES

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COMPONENT LOCATOR

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COMPONENT LOCATOR

Figure 20 — Major Component Locations for T310 Transmission

1. Main Drive Pinion Assembly

2. Main Case Shift Cover Assembly

3. Range Shift Valve Assembly

4. Compound Main Drive Gear

5. Rear Mainshaft and Synchronizer

Assembly

6. Range Shift Cylinder

7. Rear Mainshaft Bearing Cover

8. Synchronizer Assembly

9. Rear Countershaft Bearing Cover

10. Rear Countershaft Assembly

11. Front Countershaft Rear Bearing Cover

12. Reverse Idler Gear

13. Front Countershaft Assembly

14. Front Mainshaft Assembly

15. Front Countershaft Front Bearing Cover

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TROUBLESHOOTING

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TROUBLESHOOTING

TROUBLESHOOTING CHARTS

NOISY TRANSMISSION

Probable Cause Remedy

a. Low oil level a. Fill to correct level.

b. Wrong oil used b. Drain and refill with correct oil.

c. Side-mounted PTO installed too tight or too loose c. Reinstall PTO correctly.

d. Loose bell housing-to-flywheel housing capscrews d. Install new capscrews, using Loctite

e. Incorrect clutch-driven discs used e. Install correct clutch-driven discs.

f. Gears worn, chipped, rough, cracked f. Replace gears.

g. Bearings worn, cracked, corroded, galled, etc. g. Replace bearings.

h. Mismatched carrier ratios h. Install correct matched gearing.

i. Resonating (ringing) driveshaft i. Install suitable dampening material, then high-

speed balance driveshaft.

j. Driveline angles (air bags deflated) j. Correct driveline angles (allow air bags to fill).

HARD SHIFTING

Probable Cause Remedy

a. Incorrect driving practices a. Train driver in correct driving practices.

b. Low oil level b. Fill to correct level.

c. Improperly adjusted clutch, clutch linkage, clutch brake or shift

linkage

d. Wrong oil used d. Drain and refill with correct oil.

e. Remote shift linkage not lubricated e. Clean and lubricate.

f. Shift lever binding or has interference f. Relieve binding or interference.

g. Poppet balls binding in their holes g. Clean holes and balls.

h. Loose setscrews in shifters or shift forks h. Tighten to correct torque.

i. Worn spigot bearing i. Replace bearing.

j. Clutch brake ears broken j. Replace clutch brake.

k. Clutch discs worn into main drive pinion k. Replace clutch discs and main drive pinion.

l. Mainshaft snap ring or thrust washer failure l. Replace snap rings or thrust washers.

m. Improperly adjusted fourth/fifth eccentric pin m. Adjust properly.

n. PTO engaged n. Disengage PTO.

c. Adjust properly.

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Probable Cause Remedy

a. Excessive length and/or weight of gear shift lever and/or knob a. Replace with standard lever and/or knob.

b. Shift lever interference b. Remove interference.

c. Improperly adjusted remote control linkage c. Adjust properly.

d. Worn or loose mounting insulators d. Replace insulators.

e. Loose, broken or missing capscrews between clutch housing and

flywheel housing

f. Weak or broken shift rail poppet springs f. Replace springs.

g. Bent or worn shift forks g. Replace forks.

h. Broken snap rings h. Replace snap rings.

i. Shift rail bent or poppet notches worn i. Replace shift rail.

j. Worn taper or chipped teeth on sliding clutch teeth j. Replace sliding clutch and mating gear if clutch

k. Worn or damaged spigot bearing k. Replace bearing.

l. Engine flywheel housing misalignment l. Realign properly.

m. Chassis resonant ride m. Correct resonance.

TROUBLESHOOTING

GEAR DISENGAGEMENT (JUMPING OUT OF GEAR)

e. Replace capscrews, check threads in case.

teeth are damaged.

OIL LEAKS

Probable Cause Remedy

a. Oil level too high a. Drain to correct level.

b. Fill plug loose or O-ring defective or missing b. Tighten plug or correct O-ring condition.

c. Drain plug or magnetic plug loose c. Tighten plug.

d. Loose or missing capscrews d. Tighten or replace.

e. Improper lubricant used e. Drain and refill with correct oil.

f. Clogged breather f. Clean or replace.

g. Gaskets or O-rings broken, shifted or squeezed out of position g. Replace gaskets or O-rings.

h. Worn oil seals h. Replace seals.

i. O-rings or seals in air shift cylinder leaking air pressure into

transmission

BEARING FAILURE

Probable Cause Remedy

a. Dirt in system a. Clean system, replace bearings as needed,

b. Wrong grade of oil or contaminated oil b. Clean system, replace bearings as needed,

c. Excessive vibrations c. Eliminate vibrations, replace bearings.

d. Binding or seized propeller shaft slip yoke d. Clean and replace as needed.

e. Improper bearing clamping e. Replace bearings and reclamp using correct

f. Improper bearing installation (preloads, etc.) f. Replace using correct procedures.

i. Replace O-rings or seals.

flush and refill with clean oil.

procedures.

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TROUBLESHOOTING

AIR SHIFT MALFUNCTIONS

Probable Cause Remedy

a. Low system air pressure a. Wait for pressure to build back up to normal.

b. Restricted or clogged air filter in range shift valve b. Replace air filter.

c. Restricted air line (bent, squeezed, twisted, etc.) c. Re-route and/or replace air lines

d. Air lines too small d. Replace with correct size air lines.

e. Defective O-rings in air shift cylinder e. Replace O-rings.

f. Scored air shift cylinder or piston f. Repair or replace cylinder or piston.

g. Defective range shift valve and/or air shift selector valve (on shift

lever)

h. Defective synchronizer h. Repair or replace as needed.

i. Incorrect driving practices (not preselecting) i. Train driver in correct driving practices.

j. Range synchronizer friction discs worn or burned j. Replace synchronizer discs as needed.

k. Intermixed synchronizer parts k. Install matched parts.

g. Repair or replace cylinder or piston.

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MAINTENANCE

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MAINTENANCE

TRANSMISSION MAINTENANCE

Checking Oil Level

Perform oil level check when the oil is at operating temperature. The vehicle must be in a level position, both front-to-rear and side-to-side.

r Check the transmission oil level at the

intervals specified in the Maintenance and Lubrication Manual (TS494).

r To check the oil level in the transmission,

first remove the filler plug (2) from the right side of the main case.

Figure 22 — Correct Oil Level

r If oil can only be felt by reaching the finger

down into the unit, the oil level is too low.

Figure 21 — Oil Filler and Check Plug

1. Magnetic Filter Plug (Not for Level Check)

2. Oil Filler and Check Plug

r The oil must be level with the bottom of the

filler plug hole as determined by feel or by visual inspection.

Be careful not to burn your finger in hot gear oil when checking the oil level in the transmission.

Figure 23 — Incorrect Oil Level

r Add specified make-up oil, if needed, until

the oil is level with the bottom of the filler plug hole. Do NOT overfill. Use oil of the proper specification. MACK-approved gear oils can be found on the internet at www.macktrucks.com.

r Reinstall and tighten the oil filler plug

(Figure 21) as follows:

1. Check that the O-ring on the plug is not cut or damaged. Replace as necessary.

2. Install the plug and tighten to 35–50 lb-ft (47–68 N•m) torque.

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MAINTENANCE

Changing Oil

Preserve the environment! Drained gear oil is classified as a hazardous toxic material which must be recovered, handled, stored and disposed of according to applicable State or Federal guidelines.

Change Interval

r Change the oil at intervals specified in the

Maintenance and Lubrication Manual (TS494).

Draining Oil

r Before draining oil from the transmission,

the oil should be at normal operating temperature.

r Remove the magnetic drain plug from the

bottom of the transmission main case and drain the hot oil into an industry-approved recovery container.

Oil Fill

r Remove the oil filler plug (2) (Figure 25),

then fill the transmission using specified oil until the oil is level with the bottom of the filler plug hole (also see Figure 22). Do NOT overfill.

MACK-approved lubricants can be found on the internet at www.macktrucks.com the Parts and Service category.

r Reinstall and tighten the oil filler plug as

follows:

1. Check that the O-ring on the plug is not cut or damaged. Replace as necessary.

2. Install the plug and tighten to 35–50 lb-ft (47–68 N•m) torque.

, then click on

r Clean and replace the magnetic drain plug,

then torque the plug to 25–30 lb-ft (34–41 N•m).

Figure 24 — Plug Locations

Figure 25 — Oil Filler and Check Plug

1. Magnetic Filter Plug (Not for Level Check)

2. Oil Filler and Level Plug

Be sure to add oil to the transmission through the filler hole, NOT the magnetic filter plug hole. Damage to the transmission and seals can occur due to overfilling. The magnetic oil filter hole is higher on the transmission case than the filler hole.

1. Magnetic Filter Plug

2. Oil Temperature Sensor

3. Oil Drain Plug

4. Oil Fill and Level Plug

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MAINTENANCE

Magnetic Oil Filter Plug

Remove the magnetic oil filter plug and clean the magnet in the plug every time the oil is changed. Reinstall the magnetic plug. Tighten the plug to 20–23 lb-ft (27–31 N•m) torque.

Air Breather

The T310 has one air breather located on the main case shift cover. The air breather should be removed and cleaned with a suitable solvent every time the oil is changed. Also check to be sure that airflow through the breather is unobstructed. Reinstall breather into the main case shift cover and tighten until snug.

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REPAIR INSTRUCTIONS

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REPAIR INSTRUCTIONS

TRANSMISSION DISASSEMBLY PROCEDURES

[320]

Unless a complete overhaul is necessary, remove only those parts required to gain access to faulty parts. Do not disturb parts with a heavy press fit (interference fit) unless replacement is necessary. When replacement is necessary, use proper press setups and pullers to protect usable parts from damage.

External inspection of the unit before cleaning and disassembly often reveals information about existing operating conditions. This may help when diagnosing problems.

1. Clean the transmission externally and mount it in an overhaul stand. Drain the lubricant and plug any air line openings to prevent dirt from entering.

Lift and move the transmission with a hoist, using the two lifting brackets provided.

2. Disconnect the air lines attached to the range shift valve and the range shift cylinder. Air lines are installed using a push/pull type fitting and are best removed using tool kit 9032-1800trk which can be obtained through the MACK parts system. Disconnect the air lines using the following procedure:

a. Select the appropriate size release tool

from kit 9032-1800trk.

During disassembly, remember the sequence in which components and individual parts are removed from the transmission. It is good practice to keep related parts together in groups when removed. Small parts such as shims and spacers can be wired to the larger pieces with which they belong. Groups of parts can be kept together in boxes.

Keep parts such as shim packs, bearing cones, bearing retainers (covers), bearing cups and gears with the original countershaft from which they are removed. Mark each countershaft and bearing cover before removal. Mark the upper left front and rear countershafts and bearing covers (viewed from rear) as number 1. Mark the upper right front and rear countershafts and bearing covers (viewed from rear) as number 2. Mark the lower front and rear countershafts and bearing covers as number 3.

Figure 26 — Air Line Release Tools

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REPAIR INSTRUCTIONS

b. Insert the tool over the air line and

release the lines from the fittings by pushing in toward the fitting and at the same time, pulling on the hose.

5. Remove the range shift valve, interlock

sleeve, spring, pin and O-ring from the main case shift cover.

Figure 27 — Removing Air Lines

1. Air Line Removal Tool 9032-1800trk

2. Air Hose Fitting Release Ferrule

3. Label all disconnected air lines for proper reassembly.

4. Using the appropriate tools, remove the range shift valve 5/32 Allen-head screws (outer) and capscrews (inner).

Figure 29 — Removing Range Shift Components

1. Range Shift Valve

2. O-Ring

3. Interlock Sleeve

4. Interlock Spring

5. Interlock Pin

6. Shift Cover

Figure 28 — Removing Range Shift Valve Allen-Head

Screws

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REPAIR INSTRUCTIONS

6. Remove the clutch release bearing assembly, shafts, yoke and clutch brake (if equipped).

7. With transmission in neutral, remove the main case shift cover capscrews.

Figure 30 — Removing Main Case Shift Cover

Capscrews

8. Remove the main case shift cover assembly and cover gasket.

9. Remove the rear case top cover capscrews.

Figure 32 — Removing Rear Case Top Cover Capscrews

10. Remove the rear case top cover. Carefully scrape RTV sealant from around top cover opening.

Figure 31 — Removing Main Case Shift Cover

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Figure 33 — Removing Rear Case Top Cover

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To remove the drive yoke bolt, place at least two gears in both the main case and the rear case into engagement. This will lock the transmission gearing and prevent it from rotating while removing the yoke bolt.

11. Reach through the rear case top opening and verify that the synchronizer assembly sliding clutch is engaged.

12. Reach into the main case top opening and move at least two sliding clutches into engagement. This locks two different gears to the mainshaft and prevents the gears and shaft of the transmission from rotating.

REPAIR INSTRUCTIONS

14. Remove the drive yoke, using a suitable puller such as J 07804-A or equivalent.

13. Remove the drive yoke or drive flange by separating the capscrew and clamp plate.

Figure 35 — Removing Drive Yoke

15. Shift the transmission gears into neutral. Verify that the transmission is in neutral.

16. If not already done, disconnect the air lines from the range shift cylinder. Label air lines for correct installation during assembly.

Figure 34 — Removing Clamp Plate and Capscrew

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REPAIR INSTRUCTIONS

17. Remove the shift fork locking bolt.

Figure 36 — Removing Shift Fork Locking Bolt

18. Remove the four bolts that secure the shift cylinder to the rear case.

19. Remove the shift cylinder cover and O-ring.

Figure 38 — Removing Shift Cylinder Cover

20. While holding the shift fork, slide the shift cylinder from the rear of the transmission. Remove the shift cylinder-to-rear case gasket.

Figure 37 — Removing Shift Cylinder Bolts

To help remove the shift cylinder, use a plastic mallet to lightly tap on the piston to loosen the shift rail from the fork.

Figure 39 — Removing Shift Cylinder

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REPAIR INSTRUCTIONS

21. Remove the range shift cylinder gasket and discard.

Figure 40 — Removing Range Shift Cylinder Gasket

22. Number the front countershaft front bearing covers and the rear countershaft rear bearing covers, using a grease pencil. Write number 1 on the upper right front cover (viewed from front), number 2 on the upper left front cover (viewed from front) and number 3 on the lower front cover. Write number 1 on the upper left rear cover (viewed from rear), number 2 on the upper right rear cover (viewed from rear) and number 3 on the lower rear cover.

Figure 42 — Mark Rear Countershaft Bearing Covers for

Placement

23. Remove all of the rear countershaft bearing cover capscrews.

Figure 41 — Mark Front Countershaft Front Bearing

Covers for Placement

Figure 43 — Removing Rear Countershaft Bearing

Cover Capscrews

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REPAIR INSTRUCTIONS

24. Remove the jackscrew plugs from the covers.

Figure 44 — Removing Jackscrew Plugs

Pry the plugs loose using a thin knife-edge or similar tool. Do not cut through plugs during removal. Save for reuse, or replace if necessary.

26. Mark the rear countershafts as shown in Figure 46 so they can be installed in the same position during reassembly. Refer to Figure 42 for number locations.

Figure 46 — Marking Rear Countershafts

27. Remove the rear mainshaft bearing cover capscrews. Remove the jackscrew plugs from the cover.

25. Remove the rear countershaft bearing covers, shims and O-rings. Jackscrew holes are provided to assist removal.

Figure 45 — Removing Bearing Cover

Figure 47 — Removing Rear Mainshaft Bearing Cover

Capscrews

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REPAIR INSTRUCTIONS

28. Remove the rear mainshaft bearing cover. Jackscrew holes are provided to assist in removal.

Figure 48 — Removing Rear Mainshaft Bearing Cover

Using Jackscrews

29. With the transmission in a vertical position (rear case upward), remove the two capscrews located inside the rear case.

Figure 50 — Removing Outer Rear Case-to-Main Case

Capscrews

30. Remove the remaining capscrews and dowel bolts holding the rear case to the main case.

Figure 49 — Rear Mainshaft Bearing Cover Removed

When separating the rear case from the front case, make sure the transmission is in the vertical position. The rear countershafts are not supported when the case is removed. They can fall out and cause damage or personal injury.

Tap dowel bolts out of the rear case using a brass hammer or a combination of a brass hammer and a steel hammer, as long as contact is made with the brass hammer only.

Figure 51 — Removing Dowel Bolts

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REPAIR INSTRUCTIONS

Due to the relatively small size of the rear countershaft Lo gear, it is necessary to first remove each rear countershaft rear bearing cone to allow removal of the rear mainshaft. The rear countershaft bearings overhang the rear mainshaft Lo gear as shown in Figure 54. This bearing overhang prevents mainshaft removal if the bearings are not removed first.

Figure 52 — Removing Inner Rear Case-to-Main Case

Capscrews

31. Lift the rear case from the front case. Lift only the case, not the compound gear set or output shaft. Tap on the output shaft to loosen it if necessary.

Be sure unit is vertical, so that the countershafts will not fall out when the case is removed.

Figure 54 — Rear Countershaft Bearing Overhang

Page 40

Figure 53 — Removing Rear Case

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REPAIR INSTRUCTIONS

32. Using a suitable puller arrangement, such as two jaw puller J 21834-4A and bearing separator J 8176 or equivalent, remove all three rear countershaft rear bearing cones.

33. Remove the synchronizer and rear mainshaft assembly from the main drive gear. Allow the Hi-range (forward) synchronizer plates and backing plate to remain on the main drive gear.

Figure 55 — Removing Rear Countershaft Rear Bearing

Cone

Figure 56 — Removing Synchronizer and Output Shaft

1. Main Drive Gear Backing Plate

2. Hi-Range Synchronizer Plates

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REPAIR INSTRUCTIONS

34. Remove the Hi-range synchronizer plates, and the main drive gear backing plate.

35. Mark the rear countershafts (if not already done) so that they can be installed in the same location during installation.

Notice the gear timing marks. If no timing marks are present, use white paint to mark the gears in three equally spaced marks on the mainshaft. The countershaft mating gear teeth must be marked in alignment with the shaft keyway. Mark the mainshaft main drive gear-to-countershaft gears.

Figure 57 — Removing Hi-Range Synchronizer Plates

Figure 58 — Removing Main Drive Gear Backing Plate

Figure 59 — Main Drive Gear-to-Countershaft Timing

1. Lower Countershaft (No. 3)

2. Upper Left Countershaft (No. 1)

3. Upper Right Countershaft (No. 2)

4. Main Drive Gear-toCountershaft Timing Marks

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REPAIR INSTRUCTIONS

36. Remove the three rear countershafts from the rear of the transmission.

38. Remove the compound main drive gear retaining plate capscrews.

Figure 62 — Removing Compound Main Drive Gear

Retaining Plate Capscrews

39. Remove the compound main drive gear retaining plate.

Figure 60 — Removing Rear Case Countershafts

37. Remove the snap ring from inside the compound main drive gear.

To help in removing the compound main drive gear snap ring, use a pry bar to slightly lift the front mainshaft during removal. This allows more clearance and frees the snap ring from the snap ring groove.

Figure 63 — Removing Compound Main Drive Gear

Retaining Plate

Figure 61 — Removing Main Drive Gear Snap Ring

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REPAIR INSTRUCTIONS

40. Remove the compound main drive gear (with ball bearing) and the spacer from the front mainshaft.

Figure 64 — Removing Main Drive Gear from Front

Mainshaft

41. Using suitable snap ring pliers, remove the mainshaft snap ring directly behind the previously removed spacer.

Figure 66 — Spacer Mainshaft Snap Ring

42. Mark the front countershaft rear bearing covers and front countershafts for correct placement during reassembly.

Figure 65 — Removing Spacer from Front Mainshaft

1. Spacer 2. Spacer Lubrication Grooves

If not already done, use a grease pencil to number the front countershaft rear bearing covers. Write number 1 on the upper left rear cover (viewed from rear), number 2 on the upper right rear cover (viewed from rear), and number 3 on the lower rear cover. Also, mark the front countershafts (use the same numbers and locations indicated above) so that they can be installed in the same position during reassembly.

Page 44

Figure 67 — Mark Front Countershafts and Front

Countershaft Rear Bearing Covers

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REPAIR INSTRUCTIONS

43. Position the transmission case horizontally. Remove the main drive pinion bearing cover capscrews.

Figure 68 — Removing Pinion Bearing Cover Capscrews

44. Remove the main drive pinion bearing assembly. Jackscrew holes are provided to assist in removal.

45. Remove main drive pinion bearing assembly from the case.

Figure 70 — Removing Main Drive Pinion Assembly

46. Remove the exposed sliding clutch.

Figure 69 — Use Jackscrews to Remove Main Drive

Pinion Assembly

Figure 71 — Removing Sliding Clutch

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REPAIR INSTRUCTIONS

47. Remove the No. 2 (upper left) front countershaft front bearing cover capscrews.

Figure 72 — Removing No. 2 Front Countershaft Front

Bearing Cover Capscrews

48. Using jackscrews, remove the No. 2 (upper left) front countershaft front bearing cover.

Figure 74 — No. 2 Front Countershaft Front Bearing

Cover Removed

49. Remove the No. 2 (upper right) front countershaft rear bearing cover capscrews.

Figure 73 — Removing No. 2 Front Countershaft Front

Bearing Cover

Page 46

Figure 75 — Removing No. 2 Front Countershaft Rear

Bearing Cover Capscrews

10-126.bk Page 47 Thursday, December 19, 2002 10:55 AM

50. Remove the No. 2 (upper right) front countershaft rear bearing cover, using jackscrews. Remove shim with cover.

REPAIR INSTRUCTIONS

Removal is easier if the transmission is in the vertical position.

Figure 76 — Removing No. 2 Front Countershaft Rear

Bearing Cover

Figure 77 — No. 2 Front Countershaft Rear Bearing

Cover Removed

51. Using a pry bar, move the mainshaft rearward in the case to relieve pressure on the snap rings and free mainshaft gears from countershaft gears.

52. Remove the No. 2 countershaft (upper right, as viewed from rear) from the case.

Figure 78 — Removing No. 2 Countershaft from

Transmission Case

53. Using tool J 34630 or a slide hammer, remove the upper right reverse idler shaft (next to No. 2 countershaft location). To prevent damage to the reverse idler gear, catch the gear as it separates from the shaft.

Figure 79 — Using Tool J 34630 to Remove Reverse Idler

Shaft

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REPAIR INSTRUCTIONS

Figure 80 — Removing Reverse Idler Gear and Shaft

Figure 82 — Removing Snap Ring from Inside Reverse

Speed Gear

58. Remove the external-toothed and internaltoothed thrust washers from inside the reverse speed gear.

Figure 81 — Reverse Idler Gear and Shaft Removed

54. Remove the No. 1 (upper left) front countershaft rear bearing cover capscrews.

55. Using jackscrews, remove the No. 1 (upper left) front countershaft rear bearing cover. Remove shims with cover.

56. Using tool J 34630 or a slide hammer, remove the upper left reverse idler shaft (next to No. 1 countershaft). To prevent damage to the reverse idler gear, catch the gear as it separates from the shaft.

57. Remove the snap ring from inside the reverse speed gear.

Figure 83 — Removing External-Toothed Thrust Washer

Figure 84 — Removing Internal-Toothed Thrust Washer

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REPAIR INSTRUCTIONS

59. Remove the reverse gear mainshaft snap ring.

Figure 85 — Removing Reverse Gear Mainshaft Snap

Ring

1. Snap Ring 2. Reverse Gear

60. From top of case, slide the reverse gear and reverse/first sliding clutch forward.

61. Using a pry bar, move the rear end of the No. 1 (upper left) countershaft away from the mainshaft as far as possible without damaging the bearing. Block the countershaft in this position, using wadding made from rags.

Figure 87 — Moving and Blocking No. 1 (Upper Left)

Countershaft Away from Mainshaft

62. Tip the front end of the mainshaft outward and remove it from the case.

Figure 86 — Sliding Reverse Gear and Reverse/First

Clutch Forward

The reverse gear is free on the mainshaft and can fall off when handling the mainshaft assembly.

Figure 88 — Removing the Mainshaft

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REPAIR INSTRUCTIONS

63. Remove the No. 3 (lower) front countershaft rear bearing cover capscrews.

64. Using jackscrews, remove the No. 3 (lower) front countershaft rear bearing cover. Remove shims with cover.

65. Using tool J 34630 or a slide hammer, remove the lower reverse idler shaft (next to No. 3 countershaft). To prevent damage to the reverse idler gear, catch the gear as it separates from the shaft.

66. Remove the No. 1 (upper left) front countershaft by pulling and tilting the front end of the shaft upward.

67. Remove the No. 3 (lower) countershaft by pulling and tilting the front end of the shaft upward.

Figure 90 — Removing No. 3 Lower Countershaft

68. Remove the remaining No. 1 (upper right, viewed from front) and No. 3 (lower) front countershaft front bearing cover capscrews and bearing covers. Use jackscrews to remove the covers.

Figure 89 — Removing No. 1 Upper Left Countershaft

Figure 91 — Remaining No. 1 and No. 3 Front

Countershaft Bearing Covers

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REPAIR INSTRUCTIONS

TRANSMISSION COMPONENT DISASSEMBLY

[320]

Unless a complete overhaul is necessary, remove only the parts that are required to repair the assembly. Do not disturb parts that have a heavy press fit (interference fit) unless replacement of the part is necessary. When replacement is necessary, use proper pullers and press setups to prevent damage to usable parts.

Main Case Shift Cover Disassembly [323]

Figure 93 — Shift Cover Assembly

Figure 92 — Main Case Shift Cover Component Locator

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REPAIR INSTRUCTIONS

1. 4th/5th Shift Fork

2. 2nd/3rd Shift Fork

3. 1st/Reverse Shifter

4. Shifter Body Spring (Interlock)

5. Shifter Body Plunger (Interlock)

6. 1st/Reverse Shift Fork

7. 4th/5th Shifter

8. 4th/5th Rocker Pin

9. Washer

10. 4th/5th Rocker Arm

11. B ushin g

Page 52

Figure 94 — Exploded View of Main Case Shift Cover

12. Washer

13. Interlock Pin

14. Poppet Ball

15. Poppet Ball Spring

16. Interlock Rocker Hardware

17. Interlock Sleeve and O-Ring

18. Interlock Spring

19. 4th/5th Rocker Pin Hardware

20. Interlock Rocker

21. Interlock Rocker Bolt

22. Pipe Plug

23. Breather

24. Interlock Pin

25. Interlock Ball

26. 1st/Reverse Shift Rail

27. 2nd/3rd Shift Rail

28. Interlock Ball

29. Interlock Pin

30. Interlock Ball

31. 4th/5th Shift Rail

32. 1st/Reverse Shifter Ball

33. 1st/Reverse Shifter Spring

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REPAIR INSTRUCTIONS

1. Remove the nut and washers from the interlock rocker bolt.

Figure 95 — Remove Nut and Washers

2. Remove the interlock rocker and bolt from the cover.

Figure 97 — Remove Interlock Ball from Cover

4. Remove the setscrew from the first/reverse shift fork.

Figure 96 — Remove Interlock Rocker and Bolt

3. Remove the interlock ball from the cover.

Figure 98 — Removing Setscrew from First/Reverse

Shift Fork

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REPAIR INSTRUCTIONS

5. Remove the setscrew from the first/reverse shifter.

6. Slide the first/reverse shift rail to the left and remove the interlock pin.

100

Figure 99 — Removing Setscrew from First/Reverse

Shifter

Figure 100 — Sliding First/Reverse Shift Rail

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7. Remove the first/reverse shift fork from the cover.

101

REPAIR INSTRUCTIONS

Poppet balls are spring loaded and may cause injury when released.

102

Figure 101 — Removing First/Reverse Shift Fork

8. Push the first/reverse shift rail forward, using a metal bar or large screwdriver. Hold a shop towel over the top opening. The shop towel prevents the spring and ball under the rail from popping out and becoming lost.

Figure 102 — Pushing First/Reverse Shift Rail Forward

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REPAIR INSTRUCTIONS

9. Remove the poppet ball and spring from the first/reverse shift rail vertical pocket in line with the rail.

A magnet is helpful in removing the poppet ball and spring.

103

10. Remove the interlock ball from the horizontal pocket between the first/reverse shift rail and the second/third shift rail.

104

Figure 103 — Removing Poppet Ball and Spring

Figure 104 — Removing Interlock Ball

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REPAIR INSTRUCTIONS

11. Continue sliding the first/reverse shift rail forward to remove the first/reverse shifter.

105

12. Slide the first/reverse shift rail from the shift cover and at the same time, remove the fourth/fifth shift fork.

106

Figure 105 — Removing First/Reverse Shifter

Figure 106 — Removing Fourth/Fifth Shift Fork

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REPAIR INSTRUCTIONS

13. Remove the setscrew from the second/third shift fork.

107

Poppet balls are spring loaded and can cause injury when they are released.

108

Figure 107 — Removing Setscrew from Second/Third

Shift Fork

14. Push the second/third shift rail forward, using a metal bar or large screwdriver. Hold a shop towel over the top opening. The shop towel prevents the spring and ball under the rail from popping out and becoming lost.

Figure 108 — Pushing Second/Third Shift Rail Forward

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REPAIR INSTRUCTIONS

15. Remove the poppet ball and spring from the second/third shift rail vertical pocket in line with the rail.

A magnet is helpful in removing the poppet ball and spring.

109

16. Remove the interlock ball from the horizontal pocket between the second/third shift rail and the fourth/fifth shift rail.

110

Figure 109 — Removing Poppet Ball and Spring

Figure 110 — Removing Interlock Ball

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REPAIR INSTRUCTIONS

17. Remove the interlock pin from the second/ third shift rail.

111

18. Slide the second/third shift rail further forward and remove the second/third shift fork.

112

Figure 111 — Removing Pin from Second/Third Shift Rail

Figure 112 — Removing Second/Third Shift Fork

19. Continue sliding the second/third shift rail until it clears the cover.

113

Figure 113 — Removing Second/Third Shift Rail

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REPAIR INSTRUCTIONS

20. Remove the setscrew from the fourth/fifth shifter.

114

Figure 114 — Removing Setscrew from Fourth/Fifth

Shifter

21. Push the fourth/fifth shift rail forward using a metal bar or large screwdriver. Hold a shop towel over the top opening. The shop towel prevents the spring and ball under the rail from popping out and becoming lost.

115

Figure 115 — Pushing Fourth/Fifth Rail Forward

Poppet balls are spring loaded and can cause injury when they are released.

22. Continue sliding the fourth/fifth shift rail forward out of the shift cover. At the same time, remove the fourth/fifth shifter.

116

Figure 116 — Removing Fourth/Fifth Shifter

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REPAIR INSTRUCTIONS

23. Remove the poppet ball and spring from under the fourth/fifth shift rail.

A magnet is helpful in removing the poppet ball and spring.

117

25. Remove the reverse light switch from the shift cover.

119

Figure 117 — Removing Poppet Ball and Spring

24. Remove the poppet ball and spring and interlock plunger and spring from the first/ reverse shifter.

118

Figure 119 — Removing Reverse Light Switch

Figure 118 — First/Reverse Shifter Disassembled

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REPAIR INSTRUCTIONS

26. Remove the reverse light switch rod.

120

27. Remove the nut and washers from the fourth/fifth rocker pin.

121

Figure 120 — Removing Reverse Light Switch Rod

Figure 121 — Loosening Fourth/Fifth Rocker Pin Nut

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REPAIR INSTRUCTIONS

122

28. Remove the fourth/fifth rocker pin and rocker arm.

123

Figure 122 — Recovering the Lock Washer, Flat Washer

and Nut

Figure 123 — Removing Fourth/Fifth Rocker Pin and

Rocker Arm

29. Remove the shift cover breather vent.

124

Figure 124 — Removing Breather Vent

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REPAIR INSTRUCTIONS

Two-Position Range Shift Cylinder Disassembly [324]

125

Figure 125 — Range Shift Cylinder Component Locator

126

1. With the range shift cylinder in hand, tap the

end of the piston shift rail on a firm surface to begin removal of the piston/shift rail assembly.

127

Figure 127 — Piston Assembly Partially Removed

2. Continue moving the piston/shift rail out of

the cylinder housing to completely separate the piston/shift rail from the housing.

Using a small screwdriver, remove the

Tef lon

seal and O-ring from the shift rail

bore inside the cylinder housing.

128

Figure 126 — Cutaway View of Range Shift Cylinder

1. Shift Rail Seal

2. Piston Seal

3. Shift Cylinder Wiper Ring

4. Shift Cylinder Housing

5. Housing-to-Cover O-Ring

6. Cylinder Housing Cover

7. Bolt

8. Piston/Shift Rail Assembly

9. Gasket

Figure 128 — Removing Teflon® Seal and O-Ring

Expander

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REPAIR INSTRUCTIONS

3. Remove the wiper ring from the piston groove.

129

Figure 129 — Removing Wiper Ring from Piston Groove

4. Using a small screwdriver, remove the

Tef lon

seal and O-ring expander from the

second piston groove.

130

Range Shift Valve [323]

131

Figure 131 — Range Shift Valve Component Locator

132

Figure 130 — Removing Teflon® Seal and O-Ring from

Piston Grooves

Page 66

Figure 132 — Exploded View of Range Shift Valve

1. 4 mm Screw

2. Top Cover Seal

3. Top Cover

Assembly

4. Sintered Bronze Filter

5. Silicon Rubber O-Ring

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1. Remove the four (4 mm) interlock valve top

cover screws.

133

REPAIR INSTRUCTIONS

The sintered bronze filter is the only part that is serviceable on the range shift valve. Replace the range shift valve as an assembly if any internal component has failed or if the valve has become contaminated.

134

Figure 133 — Range Valve Top Cover Screws

2. Separate cover from valve housing and

remove sintered bronze filter and silicone rubber O-ring.

Figure 134 — Removing Sintered Bronze Filter

1. Sintered Bronze Filter

2. Cover

3. Valve Housing

3. Inspect top cover gasket and replace as necessary.

Page 67

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REPAIR INSTRUCTIONS

Main Drive Pinion Disassembly [322]

135

Figure 135 — Main Drive Pinion Component Locator

136

1. Remove the gasket from the main drive pinion bearing cover.

137

Figure 137 — Removing Gasket from Main Drive Pinion

Bearing Cover

2. Remove the spiral snap ring from the end of the main drive pinion shaft, inside the main drive pinion gear. Roll the snap ring out of the groove and over the shoulder of the main drive pinion, using a flat-blade screwdriver.

138

Figure 136 — Exploded View of Main Drive Pinion

1. Main Drive Pinion Shaft

2. Spigot Bearing

3. Snap Ring

4. Main Drive Pinion Gear

5. Spiral Snap Ring

6. Snap Ring

Page 68

7. Bearing

8. Spiral Snap Ring

9. Gasket

10. Pinion Bearing Cover

11. Oil Seal

Figure 138 — Removing Snap Ring from Main Drive

Pinion

The action of removing the snap ring may destroy the snap ring. Make sure a replacement snap ring is available.

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REPAIR INSTRUCTIONS

3. Remove the main drive pinion gear by lifting it straight up.

139

Figure 139 — Main Drive Pinion Gear Removed from

Shaft

4. Remove the spigot bearing snap ring from the main drive pinion, using suitable snap ring pliers.

140

5. Remove the spigot bearing from inside the end of the main drive pinion shaft.

141

Figure 141 — Spigot Bearing Removed from Main Drive

Pinion Shaft

6. Remove the main drive pinion cover bearing snap ring, using suitable snap ring pliers.

Figure 140 — Removing Spigot Bearing Snap Ring

The large snap ring is very difficult to compress and remove, and may fly off the snap ring pliers, causing injury.

142

Figure 142 — Removing Main Drive Pinion Cover

Bearing Snap Ring

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REPAIR INSTRUCTIONS

7. Separate the main drive pinion shaft and bearing assembly from the main drive pinion bearing cover.

143

The action of removing the spiral snap ring may destroy the snap ring. Make sure a replacement snap ring is available.

9. Place the main drive pinion shaft and bearing into a suitable press and remove the bearing.

145

Figure 143 — Removing Main Drive Pinion Shaft and

Bearing from Cover

8. Remove the spiral snap ring securing the bearing to the main drive pinion shaft. Using a small flat-blade screwdriver, roll the spiral snap ring out of the groove until released.

144

Figure 144 — Removing Spiral Snap Ring from Main

Drive Pinion

Figure 145 — Pressing Bearing off Main Drive Pinion

Shaft

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REPAIR INSTRUCTIONS

10. Thoroughly clean the bearing and inspect for damage.

11. Remove the oil seal from the main drive pinion bearing cover, using a hammer and a blunt punch.

Removing the oil seal destroys the seal. Make sure a replacement oil seal is available.

146

The splines on the mainshaft are usually not aligned for the whole length of the shaft. The recommended procedure is to remove the second, third and fifth speed gears, gear thrust washers and snap rings, and second/third sliding clutch from the front of the shaft (parts shown to the left of the arrows). Remove the remaining reverse and first speed gears and components from the rear of the shaft (parts shown to the right of the arrows).

148

Figure 146 — Removing Bearing Cover Oil Seal

Front Mainshaft Disassembly [322]

147

Figure 147 — Front Mainshaft Component Locator

Figure 148 — View of Mainshaft and Gears

1. 5th/10th Gear

2. 3rd/8th Gear

3. Sliding Clutch

4. 2nd/7th Gear

5. 1st/6th Gear

6. Sliding Clutch

7. Reverse Gear

Page 71

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REPAIR INSTRUCTIONS

149

1. Mainshaft Snap Ring

2. Internal-Toothed Thrust Washer

3. Fifth (10th) Speed Gear

4. External-Toothed Thrust Washer

5. Gear Snap Ring

6. Spigot-Bearing Inner Race Snap Ring

7. Spigot-Bearing Inner Race

8. Front Mainshaft

9. Spigot Bearing

10. Spigot Bearing Snap Ring

11. Third (8th) Speed Gear

Page 72

Figure 149 — Exploded View of Front Mainshaft

12. Gear Snap Ring

13. External-Toothed Thrust Washer

14. Internal-Toothed Thrust Washer

15. Mainshaft Snap Ring

16. Sliding Clutch

17. Mainshaft Snap Ring

18. Internal-Toothed Thrust Washer

19. Second (7th) Speed Gear

20. External-Toothed Thrust Washer

21. Gear Snap Ring

22. Gear Snap Ring

23. External-Toothed Thrust Washer

24. First (6th) Speed Gear

25. Internal-Toothed Thrust Washer

26. Mainshaft Snap Ring

27. Sliding Clutch

28. Mainshaft Snap Ring

29. Internal-Toothed Thrust Washer

30. Reverse Speed Gear

31. External-Toothed Thrust Washer

32. Gear Snap Ring

33. Mainshaft Snap Ring

34. Spacer

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REPAIR INSTRUCTIONS

1. If not already done, remove the reverse speed gear mainshaft snap ring, using suitable snap ring pliers (fifth snap ring groove from the front of the mainshaft).

150

3. Remove the first/reverse sliding clutch from the mainshaft.

152

Figure 152 — Removing First/Reverse Sliding Clutch

from Mainshaft

4. Using suitable snap ring pliers, remove the snap ring retaining the first (6th) speed gear to the mainshaft (fourth groove from the front of the mainshaft).

153

Figure 150 — Removing Reverse Gear Mainshaft Snap

Ring

2. Slide the reverse gear off the mainshaft.

151

Figure 151 — Removing Reverse Gear from Mainshaft

Figure 153 — Removing First Gear Mainshaft Snap Ring

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REPAIR INSTRUCTIONS

5. Remove the internal- and external-toothed thrust washers from inside the first (6th) speed gear.

154

Figure 154 — Removing Internal-Toothed and

External-Toothed Thrust Washers

6. Slide first (6th) speed gear from mainshaft.

155

156

Figure 155 — Removing First Speed Gear

7. Using suitable snap ring pliers, remove the snap ring from the outside groove, inside the first (6th) speed gear.

8. Working at the opposite end of the mainshaft and using suitable snap ring pliers, remove the snap ring that retains the fifth (10th) speed gear to the mainshaft (first groove from the front of the mainshaft).

Figure 156 — Removing Fifth Speed Gear Mainshaft

Snap Ring

9. Remove the internal- and external-toothed thrust washers and fifth (10th) speed gear from the mainshaft.

157

Figure 157 — Removing Internal- and External-Toothed

Thrust Washers and Fifth Speed Gear

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10. Remove the snap ring from inside the fifth (10th) speed gear.

158

Figure 158 — Removing Snap Ring Inside Fifth Speed

Gear

11. Slide the third (8th) speed gear from the mainshaft and remove the snap ring from inside the gear, using suitable snap ring pliers.

159

160

Figure 160 — Removing Third Speed Gear External- and

Internal-Toothed Thrust Washers

13. Using suitable snap ring pliers, remove the third (8th) speed gear mainshaft snap ring (second groove from the front of the mainshaft).

161

Figure 159 — Removing Third Speed Gear

12. Remove the third (8th) speed gear externaland internal-toothed thrust washers.

Figure 161 — Removing Third Speed Gear Mainshaft

Snap Ring

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14. Remove the second/third sliding clutch from the mainshaft. Slide straight off splines.

162

Figure 162 — Removing Second/Third Sliding Clutch

15. Using suitable snap ring pliers, remove the second (7th) speed gear mainshaft snap ring (third groove from the front of the mainshaft).

163

16. Remove the second (7th) speed gear internal- and external-toothed thrust washers.

164

Figure 164 — Removing Internal- and External-Toothed

Thrust Washers

17. Remove the second (7th) speed gear from the mainshaft. Slide straight off the shaft.

165

Figure 163 — Removing Second Speed Gear Mainshaft

Snap Ring

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Figure 165 — Removing Second Speed Gear from

Mainshaft

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18. Remove the second (7th) speed gear snap ring, using suitable snap ring pliers.

166

Figure 166 — Removing Second Speed Gear Snap Ring

19. Remove the snap ring that retains the spigot bearing inner race to the mainshaft, using suitable snap ring pliers.

167

20. Remove the spigot bearing inner race, using a suitable puller.

168

Figure 168 — Removing Spigot Bearing Inner Race

21. If inspection reveals the need to remove and replace the spigot bearing (rear end of shaft), first remove the snap ring and then the bearing.

169

Figure 167 — Removing Spigot Bearing Inner Race Snap

Ring

Figure 169 — Removing Front Mainshaft Rear Spigot

Bearing

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Rear Mainshaft and Synchronizer Disassembly [322]

170

Figure 170 — Rear Mainshaft and Synchronizer

Component Locator

171

1. Remove the synchronizer assembly from the rear mainshaft.

172

Figure 171 — Exploded View of Rear Mainshaft and

Synchronizer Assembly

Figure 172 — Removing Synchronizer Assembly

2. Remove the reaction discs and the friction discs from inside the Lo-range gear.

173

1. Synchronizer Assembly

2. Reaction Discs

3. Friction Discs

4. Snap Ring

5. Lo-Range Gear

6. Snap Ring

Page 78

7. Internal-Toothed Thrust Washer

8. Lo-Range Gear Hub

9. Snap Ring

10. Spigot Bearing Inner Race

11. Rear Mainshaft

Figure 173 — Removing Reaction Disc

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174

Figure 174 — Removing Friction Disc

3. Remove the spiral snap ring securing the Lo-range gear to the Lo-range gear hub and then remove the Lo-range gear.

175

4. Remove the snap ring from inside the Lo-range gear hub.

176

Figure 176 — Removing Gear Hub Snap Ring

5. Remove the gear hub thrust washer from the rear mainshaft.

177

Figure 175 — Removing Lo-Range Gear Snap Ring

Figure 177 — Removing Thrust Washer

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6. Remove the Lo-range gear hub from the rear mainshaft.

178

Figure 178 — Removing Lo-Range Gear Hub

8. Press the spigot bearing inner race off the front end of the rear mainshaft using bearing separator J 22912-01 or equivalent.

180

7. Remove the spigot bearing inner race snap ring from the front of the rear mainshaft.

179

Figure 179 — Removing Snap Ring

Figure 180 — Removing Snap Ring

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Synchronizer Disassembly [322]

181

Figure 181 — Synchronizer Assembly Component

Locator

182

1. Remove the 12-point screws and threaded and nonthreaded inserts from the synchronizer assembly.

183

Figure 183 — Removing 12-Point Screws

2. Remove the clutch housing from the assembly.

3. Remove the three support tubes and preload springs from the synchronizer assembly.

184

Figure 182 — Exploded View of Synchronizer

1. 12-Point Screw

2. Nonthreaded Insert

3. Clutch Housing

4. Synchronizer Pin

5. Sliding Clutch

6. Synchronizer Pin

7. Clutch Housing

8. Threaded Insert

9. Support Tube

10. Preload Spring

Figure 184 — Remove Synchronizer Support Tubes and

Preload Springs

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4. Remove the sliding clutch from the remaining clutch housing.

As you remove the synchronizer sliding clutch and pins, notice that the pins and the sliding clutch are marked with the letter “R”, which stands for “Rear.” All the R marks on either end of the pins are placed on the same side of the sliding clutch marked with the letter R. During reassembly, make sure to coordinate all R marks on both the pins and sliding clutch of the synchronizer assembly. All R marks must face the rear of the transmission when installed.

185

5. Remove the synchronizer pins from the remaining clutch housing.

186

Figure 186 — Removing Synchronizer Pins

6. Thoroughly clean the synchronizer assembly and inspect for damage.

Figure 185 — Letter “R” on Sliding Clutch and

1. “R” on Sliding Clutch, Faces Rearward

Synchronizer Pins

2. “R” on Synchronizer Pins, Faces Rearward

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Rear Mainshaft Bearing Cover Disassembly [321]

187

Figure 187 — Rear Mainshaft Bearing Component

Locator

188

1. Remove the gasket from the bearing cover.

2. Remove the snap ring securing the bearing in the rear mainshaft bearing cover, using suitable snap ring pliers.

189

Figure 189 — Removing Snap Ring from Rear Mainshaft

Bearing Cover

3. Remove the bearing from the rear mainshaft bearing cover, using a suitable puller.

190

Figure 188 — Exploded View of Rear Mainshaft Bearing

1. Bearing Cover

2. Oil Seal

3. Gasket

Cover

4. Bearing

5. Snap Ring

Figure 190 — Removing Bearing from Bearing Cover

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4. Remove the oil seal from the rear mainshaft bearing cover, using a hammer and blunt punch. Drive the seal out from the opposite side. Discard the cover gasket.

191

Figure 191 — Using Hammer and Blunt Punch to

Remove Oil Seal

193

Figure 193 — Exploded View of Compound Main Drive

Gear

This action destroys the oil seal. Make sure a replacement oil seal is readily available.

5. Thoroughly clean the rear mainshaft bearing and bearing cover, and inspect for damage.

Compound Main Drive Gear Disassembly [322]

192

1. Bearing and Snap Ring 2. Main Drive Gear

1. Press the bearing off the main drive gear, using a suitable press tool.

194

Figure 192 — Compound Main Drive Gear Component

Locator

Page 84

Figure 194 — Pressing off Bearing

2. Thoroughly clean the main drive gear and bearing and inspect for damage.

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Front Countershaft Front Bearing Cover Disassembly [321]

195

Figure 195 — Front Countershaft Front Bearing Cover

Component Locator

196

The following disassembly procedure applies to all front countershaft front bearing covers.

1. Remove the O-ring from the shoulder of the

front countershaft front bearing cover.

197

Figure 197 — Removing O-Ring from Shoulder of Front

Countershaft Front Bearing Cover

2. Remove the bearing cone from the front

countershaft front bearing cover, using a suitable puller.

198

Figure 196 — Exploded View of Front Countershaft

1. O-Ring

2. Bearing Cone

Front Bearing Cover

3. Front Bearing Cover

Figure 198 — Removing Bearing Cone from Front

Countershaft Front Bearing Cover

3. Thoroughly clean the bearing cover and

inspect for damage.

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Front Countershaft Disassembly [322]

199

Figure 199 — Front Countershaft Component Locator

200

The following disassembly procedure applies to all three front countershafts.

The reverse, first and second speed gears on the countershaft must be pressed off the rear end of the shaft. The forward end of the shaft is slightly larger in diameter than the rear. If you try to press any of these gears on or off the forward end of the shaft, the gears can crack, and may fragment explosively, spraying metal pieces outward. This can cause severe injury or death.

1. Press the front countershaft main drive gear off the front of the countershaft.

201

Figure 200 — Exploded View of Front Countershaft

1. Bearing Cup

2. Main Drive Gear

3. Fifth (10th) Speed Gear

4. Third (8th) Speed Gear

5. Spacer — Front

6. Front Countershaft

7. Key

Page 86

8. Bearing Cone

9. Reverse Speed Gear

10. Spacer — Rear

11. First (6th) Speed Gear

12. Second (7th) Speed Gear

Figure 201 — Pressing Main Drive Gear off Shaft

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2. Press the fifth (10th) speed gear off the front of the countershaft.

202

3. Press the front countershaft third (8th) speed gear off the front of the countershaft.

203

Figure 202 — Pressing Fifth Speed Gear off Shaft

Figure 203 — Pressing Third Speed Gear off Shaft

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4. Remove the front spacer located between the third and second speed gears from the shaft.

204

205

Figure 205 — Pressing off Reverse Gear and Rear

Bearing Cone

Figure 204 — Removing Spacer

5. Press the reverse gear and rear bearing cone off the rear end of the countershaft.

6. In a similar manner, press off the first (6th) and second (7th) speed gears from the rear of the countershaft. The previous warning also applies when pressing these gears off the countershaft.

7. Remove the key from the keyway of the front countershaft.

206

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Figure 206 — Removing Key

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8. Remove the bearing cup from the front countershaft main drive gear, using a suitable puller.

207

Front Countershaft Rear Bearing Cover Disassembly [321]

208

Figure 208 — Front Countershaft Rear Bearing Cover

Component Locator

209

Figure 207 — Removing Bearing Cup from Main Drive

Gear

Figure 209 — Exploded View of Front Countershaft Rear

1. Front Bearing Cup

2. Bearing Cover

Bearing Cover

3. Rear Bearing Cup

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1. Remove the front and rear bearing cups from the front countershaft rear bearing cover.

210

Figure 210 — Removing Front Bearing Cup

211

Rear Countershaft Disassembly [322]

212

Figure 212 — Rear Countershaft Component Locator

213

Figure 211 — Removing Rear Bearing Cup

2. Thoroughly clean the bearing cover and inspect for damage.

Page 90

Figure 213 — Exploded View of Rear Countershaft

1. Front Bearing Cone

2. Main Drive Gear

3. Key

4. Rear Bearing Cone

5. Rear Countershaft (Lo-Range Gear Integral with Shaft)

Do not attempt to press-remove the Lo-range gears off these rear countershafts. This gear is integral with the shaft and could fragment explosively when pressing action is attempted.

MACK T310 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual