MACK T313, T318 Service Manual

TRANSMISSIONS

T313–T318(L)(LR)(21)(L21)(LR21) SERVICE MANUAL

OCTOBER 2008 (REVISED)

10-123

TRANSMISSIONS

T313–T318(L)(LR)(21)(L21)(LR21)

SERVICEMANUAL

T313–T318(L)(LR)

T313–T318(21)(L21)(LR21)

OCTOBER 2008		© MACK TRUCKS, INC. 2008
(REVISED — SUPERSEDES ISSUE DATED JULY 2003)		10-123

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

TABLE OF CONTENTS

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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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 DESCRIPTION AND OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 T313–T318(L)(LR)(21)(L21)(LR21) Transmissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 T313 Series Gear Ratios and Shift Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 T318 Series Gear Ratios and Shift Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 T313(L)(LR)(21)(L21)(LR21) Shifting Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 T318(L)(LR)(21)(L21)(LR21) Shifting Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Guidelines for PTO Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 T313 Power Flow Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 T318 Power Flow Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

COMPONENT LOCATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 TRANSMISSION MAJOR COMPONENT LOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 TROUBLESHOOTING CHARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

TRANSMISSION MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Checking Oil Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Changing Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Magnetic Oil Filter Plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Air Breather(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

REPAIR INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 TRANSMISSION DISASSEMBLY PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 TRANSMISSION COMPONENT DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Main Case Shift Cover Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Rear Case Shift Cover Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 Three-Position Range Shift Cylinder Disassembly (Compound Neutralizing) . . . . . . . . . . . . . . 86 Two-Position Range Shift Cylinder Disassembly (Compound Non-Neutralizing) . . . . . . . . . . . 89 Range Shift Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Main Drive Pinion Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Front Mainshaft Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Rear Mainshaft (Output Shaft) and Synchronizer Disassembly . . . . . . . . . . . . . . . . . . . . . . . . 103 Rear Mainshaft Bearing Cover Disassembly: T313–T318(L)(LR) . . . . . . . . . . . . . . . . . . . . . . 115 Rear Output Housing Disassembly: T313–T318(21)(L21)(LR21) . . . . . . . . . . . . . . . . . . . . . . 117 Front Countershaft Front Bearing Cover Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 Front Countershaft Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 Front Countershaft Rear Bearing Cover Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 Rear Countershaft Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Rear Countershaft Bearing Cover Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 Reverse Idler Gear Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125

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TABLE OF CONTENTS
INSPECTION OF PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	126
Inspection and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	126
Bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	126
Gears . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	126
Shifter Forks, Sliding Clutches and Shift Rails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	126
Oil Seals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	127
General Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	128
General Reassembly Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	128
TRANSMISSION COMPONENT REASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	129
Reverse Idler Gear Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	129
Rear Countershaft Bearing Cover Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	130
Rear Countershaft Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	131
Front Countershaft Rear Bearing Cover Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	133
Front Countershaft Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	134
Front Countershaft Front Bearing Cover Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	139
Rear Mainshaft Bearing Cover Reassembly: T313–T318(L)(LR) . . . . . . . . . . . . . . . . . . . . . .	140
Rear Output Housing Reassembly: T313–T318(21)(L21)(LR21) . . . . . . . . . . . . . . . . . . . . . .	142
Rear Mainshaft (Output Shaft) and Synchronizer Reassembly . . . . . . . . . . . . . . . . . . . . . . . .	145
Front Mainshaft Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	159
Main Drive Pinion Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	168
Range Shift Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	171
Two-Position Range Shift Cylinder Reassembly (Compound Non-Neutralizing) . . . . . . . . . . .	173
Three-Position Range Shift Cylinder Reassembly (Compound Neutralizing) . . . . . . . . . . . . .	178
Rear Case Shift Cover Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	181
Main Case Shift Cover Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	184
TRANSMISSION REASSEMBLY PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	198

SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223

TRANSMISSION SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224

Torque Specifications, T313–T318(L)(LR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224

Torque Specifications, T313–T318(21)(L21)(LR21) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226

Gear Identification, T313–T318(21) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228

Gear Identification, T313–T318(L)(LR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230

Gear Identification, T313–T318(L21)(LR21) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232

Fits and Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234

General Tolerances, T313–T318(L)(LR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

General Tolerances, T313–T318(21)(L21)(LR21) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236

Transmission Specifications and Capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237

SCHEMATIC & ROUTING DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 AIR PIPING DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240

T313–T318(L)(LR)(21)(L21)(LR21) Air Control without Compound Neutralizing for

PTO Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 T313–T318(L)(LR)(21)(L21)(LR21) Air Control with Compound

Neutralizing for PTO Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242

SPECIAL TOOLS & EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245 SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246

DISASSEMBLED VIEWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247 TRANSMISSION DISASSEMBLED VIEWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248

INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257

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NOTES

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INTRODUCTION

INTRODUCTION

Page 1

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:

Danger indicates an unsafe practice that could result in death or serious personal injury. Serious personal injury is considered to be permanent injury from which full recovery is NOT expected, resulting in a change in life style.

Warning indicates an unsafe practice that could result in personal injury. Personal injury means that the injury is of a temporary nature and that full recovery is expected.

Caution indicates an unsafe practice that could result in damage to the product.

Note indicates a procedure, practice, or condition that must be followed in order for the vehicle or component to function in the manner intended.

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

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INTRODUCTION

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, apply the parking brakes, and push in the clutch pedal. Failure to follow these instructions could produce unexpected vehicle movement, which can result in serious personal injury or death.

2.Before working on a vehicle, place the transmission in neutral, set the parking brakes, and block the wheels. Failure to follow these instructions could produce unexpected vehicle movement, which can result in serious personal injury or death.

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.

Do not work under a vehicle that is supported only by a hydraulic jack. The hydraulic jack could fail suddenly and unexpectedly, resulting in severe personal injury or death. Always use jackstands of adequate capacity to support the weight of the vehicle.

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.

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.

Perform all service work on a flat, level surface. Block wheels to prevent vehicle from rolling.

DO NOT wear loose-fitting or torn clothing. Remove any jewelry before servicing vehicle.

ALWAYS wear safety glasses and protective shoes. Avoid injury by being aware of sharp corners and jagged edges.

Use hoists or jacks to lift or move heavy objects.

NEVER run engine indoors unless exhaust fumes are adequately vented to the outside.

Be aware of hot surfaces. Allow engine to cool sufficiently before performing any service or tests in the vicinity of the engine.

Keep work area clean and orderly. Clean up any spilled oil, grease, fuel, hydraulic fluid, etc.

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.

Do not store natural gas powered vehicles indoors for an extended period of time (overnight) without first removing the fuel.

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, the 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

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

Example of Numerical Code

Page 5

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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INTRODUCTION

	Conversion Units			Multiply By:
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)	(°F − 32) x 0.556
Degrees Celsius (°C)		to	Degrees Fahrenheit (°F)	(1.8 x °C) + 32

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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 H2O)		to	Kilopascals (kPa)	0.2491
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 H2O)	4.01445
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

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VISUAL IDENTIFICATION

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.

1.Unit Symbol Identification T = transmission

3 = 300 series

13/18 = useable forward speeds L = low forward gear

R = low reverse gear

21 = 2100 lb-ft torque capacity

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)

Figure 2 — Unit Identification Stamping

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VISUAL IDENTIFICATION

Figure 3 — Cutaway View of T313/T318 Transmission

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VISUAL IDENTIFICATION

Figure 4 — Cutaway View of T313L/T318L Transmission

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VISUAL IDENTIFICATION

Figure 5 — Cutaway View of T313LR/T318LR Transmission

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VISUAL IDENTIFICATION

Figure 6 — Cutaway View of T313L21/T318L21 Transmission

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VISUAL IDENTIFICATION

Figure 7 — Cutaway View of T313LR21/T318LR21 Transmission

Transmission model not shown:

T31321/T31821

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NOTES

Page 16

DESCRIPTION AND OPERATION

DESCRIPTION AND OPERATION

Page 17

DESCRIPTION AND OPERATION

DESCRIPTION AND

OPERATION

T313–T318(L)(LR)(21)(L21)(LR21)

Transmissions

DESCRIPTION

The T313/T318 series transmissions are a member of a new family of MACK transmissions designated as MAXITORQUE® ES (T300) series transmissions. 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:

New and revised gear ratios for greater overall range and versatility

Lower “LOs” in forward and reverse for superior site maneuvering

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

Enhanced durability

Weight reduction versus the previous series transmissions

The T313/T318 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 T313/T318 transmission is also a triple-countershaft unit. The rear case consists of Lo-range and Hi-range gear sets plus a splitter section.

A single gearshift lever is used to shift through a “progressive-H” shift pattern. In addition, an air-operated valve (with two selectors), mounted on the shift lever, is used to shift both the range gears and splitter gears in the compound. A plate-type synchronizer is used to range shift between the Hi-range and Lo-range gear sets.

T313 series transmission provides two reverse speeds, while the T318 series provides three reverse speeds. The reverse speeds are produced by the gear sets in the main case and by means of the Lo-range, Hi-range and splitter gearing in the compound case.

The T318 series transmission has 18 forward speeds produced by five forward gear sets in the main case (Lo, first, second, third and fourth), along with a splitter gear set and the Lo-range and Hi-range gear sets. With the Lo-range gear set in the compound selected, the five main case gear sets can be split shifted to obtain 10 forward speeds, starting with Lo gear. The main case Lo gear is used only when the compound is in Lo range and is not used in Hi range. To obtain eight additional forward speeds, the Hi-range gear set in the compound is selected and the main case gearshift lever positions of first through fourth are split shifted a second time, for a total of

18 forward speeds.

The T313 series transmission has 13 forward speeds produced by the same five gear sets (Lo, first, second, third and fourth) as the T318 series. The T313 series, however, is not split shifted while the compound is in the Lo-range. This provides five forward, Lo-split, Lo-range speeds. To obtain the remaining eight forward speeds, the compound Hi-range gear set is selected and the main case gearshift lever positions of first through fourth are repeated, only this time, split shifted for a total of 13 forward speeds. Refer to “T313(L)(LR)(21)(L21)(LR21) Shifting Instructions” on page 23 or “T318(L)(LR)(21)(L21)(LR21) Shifting Instructions” on page 24 for complete shifting procedure information.

The main case and the bell housing of both the 13and the 18-speed transmissions are constructed of a one-piece casting, made from aluminum and heat-treated for strength.

The main case also has sixand eight-bolt openings that allow for the addition of Power Take-Off (PTO) units. PTO operation is off the countershaft fourth (8th) speed gear. The rear case has sixand eight-bolt openings also, to allow for additional PTO units. PTO operation is off the Hi-range/Hi-split gear.

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DESCRIPTION AND OPERATION

Provisions for Rear-Mounted Power Take-Off (RMPTO) units are available on these transmissions. The output speed (as a percentage of engine speed) of the RMPTO units, depends on which T300 transmission it is mounted on and is fixed at that percentage, regardless of which transmission gear is selected. The PTO speed to engine RPM percentage for the T313 and T318 series transmissions are all at 70 percent.

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

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.

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.

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 9 — Splash Lubrication

Figure 8 — Equal Torque Distribution

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DESCRIPTION AND OPERATION

TRANSMISSION CASE OIL COOLER LINE PLUGS

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 T313/T318 series 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.

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.

Figure 10 — Transmission Case Oil Cooler Line Plugs

1. Outlet Plastic Cap	2. Suction Tube Plug

Figure 11 — Plug Locations

1.	Magnetic Filter Plug	3.	Oil Drain Plug
2.	Oil Temperature Sensor	4.	Oil Fill and Level Plug

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DESCRIPTION AND OPERATION

T313 Series Gear Ratios and Shift Pattern

Figure 12 — T313(L)(LR)(21)(L21)(LR21) Shift Pattern

T313(L)(LR)(21)(L21)(LR21) SHIFT PATTERN

Gear Position				T313(L)(L21)	T313(LR)(LR21)
(Main Box)	Splitter	Range	T313(21)Ratios	Ratios	Ratios
Lo	Lo	Lo	13.44	16.42	16.42
1	Lo	Lo	8.78	8.78	8.78
2	Lo	Lo	6.28	6.28	6.28
3	Lo	Lo	4.52	4.52	4.52
4	Lo	Lo	3.22	3.22	3.22
			Range Shift
5	Lo	Hi	2.29	2.29	2.29
5	Hi	Hi	1.94	1.94	1.94
6	Lo	Hi	1.64	1.64	1.64
6	Hi	Hi	1.39	1.39	1.39
7	Lo	Hi	1.18	1.18	1.18
7	Hi	Hi	1.00	1.00	1.00
8	Lo	Hi	0.84	0.84	0.84
8	Hi	Hi	0.71	0.71	0.71
			Reverse
R	Lo	Lo	15.91	15.91	28.98
R	Lo	Hi	4.15	4.15	N/A
R	Hi	Hi	3.52	3.52	6.41

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DESCRIPTION AND OPERATION

T318 Series Gear Ratios and Shift Pattern

Figure 13 — T318(L)(LR)(21)(L21)(LR21) Shift Pattern

T318(L)(LR)(21)(L21)(LR21) SHIFT PATTERN

Gear Position				T318(L)(L21)	T318(LR)(LR21)
(Main Box)	Splitter	Range	T318(21) Ratios	Ratios	Ratios
Lo	Lo	Lo	13.44	16.42	16.42
Lo	Hi	Lo	11.40	13.93	13.93
1	Lo	Lo	8.78	8.78	8.78
1	Hi	Lo	7.45	7.45	7.45
2	Lo	Lo	6.28	6.28	6.28
2	Hi	Lo	5.33	5.33	5.33
3	Lo	Lo	4.52	4.52	4.52
3	Hi	Lo	3.83	3.83	3.83
4	Lo	Lo	3.22	3.22	3.22
4	Hi	Lo	2.73	2.73	2.73
			Range Shift
5	Lo	Hi	2.29	2.29	2.29
5	Hi	Hi	1.94	1.94	1.94
6	Lo	Hi	1.64	1.64	1.64
6	Hi	Hi	1.39	1.39	1.39
7	Lo	Hi	1.18	1.18	1.18
7	Hi	Hi	1.00	1.00	1.00
8	Lo	Hi	0.84	0.84	0.84
8	Hi	Hi	0.71	0.71	0.71
			Reverse
R	Lo	Lo	15.91	15.91	28.98
R	Hi	Lo	13.49	13.49	24.58
R	Lo	Hi	4.15	4.15	N/A
R	Hi	Hi	3.52	3.52	6.41

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DESCRIPTION AND OPERATION

T313(L)(LR)(21)(L21)(LR21) Shifting

Instructions

The shifting instructions in this Service Manual may have been upgraded and superseded due to Mack’s continuous program of testing and evaluating to provide the best possible product.

Be sure to check the latest shifting instructions found in the on-line Operator’s Handbooks located on the Mack website at www.macktrucks.com.

The T313 series transmission is a range and split shifted unit which has 12 forward gears with an extra Lo gear in the Lo range. It features an air-operated Lo range, Hi range and splitter section in the rear compound, controlled by a range selector and splitter selector on the shift lever. The Lo range provides five low ratios (includes Lo gear). In Hi range there are eight additional forward gears that can be obtained. Reverse gear can be used in Lo and Hi ranges for a total of two reverse speeds:

Lo Range — Lo Split

Hi Range — Hi Split

When making a split shift (from one gear to the next gear), the splitter selector must not be actuated, either up or down, until the main case is in neutral. When making a split shift (in the same gear), especially under heavy load, the splitter will not shift until driveline torque is relieved by depressing the clutch pedal or backing off the throttle. An audible shift is heard (engine speed drops approximately 200 rpm).

When making a range shift, it is important to preselect the shift. This means that the range selector must be moved to the next position (up or down) before the gearshift lever is moved. Preselect the range shift and then move the shift lever through neutral to the desired gear position. As the lever passes through neutral, the range shift is automatically completed.

UPSHIFTING (NORMAL HIGHWAY)

To begin, position the shift lever in neutral and move the range selector to the Hi position (a mechanical interlock prevents splitter selector movement to the Lo position). Next, select Lo split using the splitter selector. Then select Lo range using the range selector.

Refer to the shift pattern and move the shift lever to the Lo speed gear (Lo range, Lo split) position. Apply the accelerator, engage the clutch and accelerate to governed speed. Shift up through first, second, third and fourth speed gears, double-clutching between the gears.

Continue shifting while in fourth gear (Lo range, Lo split) by preselecting Hi range with the range selector and then moving the shift lever through neutral to the fifth gear position. As the lever moves through neutral, the range shift to Hi will be completed. The transmission is now in fifth gear (Hi range, Lo split). To continue, use a combination of splitter selector and shift lever to shift to fifth (Hi range, Hi split), sixth (Hi range, Lo split), sixth (Hi range, Hi split) and so on, until eighth (Hi range, Hi split) is achieved, double-clutching between the gears.

To upshift from Lo-split to Hi-split (in the same gear), accelerate the engine to governed speed, move the splitter switch to Hi (preselect), then depress the clutch and back off the accelerator pedal. Reapply the accelerator and engage the clutch when the audible shift is heard, or when the engine speed falls by approximately 200 rpm. Depressing the clutch may not be necessary to break the driveline torque, but this will vary with road conditions.

To upshift from a Hi-split gear to the next higher gear's Lo-split (in Hi-range), accelerate the engine to governed speed, break the driveline torque by depressing the clutch or backing off the accelerator pedal, then move the splitter switch to Lo and, at the same time, move shift lever through neutral to the next higher gear. Note that the splitter switch must not be actuated down to the Lo position until the main box is in neutral.

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