Eaton Transmission CL-450 Service Manual

Service Manual

Fuller Mid Range Transmissions
TRSM0196

October 2007

For parts or service call us

Pro Gear & Transmission, Inc.

1 [phone]

[phone]

[e-mail]

906 W. Gore St.

Orlando, FL 32805

Caution -

Before towing the vehicle, be sure to lift the rear wheels off the ground or disconnect the

driveline to avoid damage to the transmission during towing.

FOREWARD

This manual has been prepared to provide the customer and the maintenance personnel with information and instruc­tions on the maintenance and repair of the CLARK® Transmission.
Extreme care has been exercised in the design, selection of materials and manufacturing of these units. The slight out­lay in personal attention and cost required to provide regular and proper lubrication, inspection at stated intervals, and
such adjustments as may be indicated will be reimbursed many times in low cost operation and trouble free service.
In order to become familiar with the various parts of the transmission, its principle of operation, troubleshooting and
adjustments, it is urged that the service person study the instructions in this manual carefully and use it as a reference
when performing maintenance and repair operations.
Whenever repair or replacement of components parts is required, only Clark-approved parts as listed in the applicable
parts manual should be used. Use of “will-fit” or non-approved parts may endanger proper operation and performance
of the equipment. The Clark Equipment Company does not warrant repair or replacement parts, nor failures resulting
from the use thereof, which are not supplied by or approved by the Clark Equipment Company.

IMPORTANT: Always furnish the Distributor with the transmission serial and model number when ordering parts.

The CL455 is our “soft fourth” transmission, with the 28 percent step from fourth to fifth. The soft fourth allows the use
of a two speed axle without the confusing swap shift in fourth and fifth speeds.

The CL457 is the conventional short fourth 5-speed, for those that still prefer it.

And the CL450 is a straight 5-speed with an 8 to 1 low and reverse ratio . . . a real benefit when a steep grade must be
negotiated.

MODELS

CL455

Speed

Fifth Direct Direct Direct

Fourth 1.28 1.17 1.48

Third 2.13 2.13 2.48

Second 3.78 3.78 4.35

First 6.99 6.99 8.05

Reverse 6.99 6.99 8.05

Nomenclature-CL Stands for Clark. 1st number stands for nominal torque capacity (nom. 400/lb./ft.). 2nd number
is number of forward speeds. 3rd number denotes specific gear set.

Constant mesh in all gears, including low and reverse, is a CL450 feature as is helical gearing throughout, including low
and reverse.

The Clark split-pin synchronizer is used in 2nd, 3rd 4th and 5th gears. Greater bearing capacity in the CL450 is achieved
by the use of numerous needle roller bearings, and tapered roller bearings at main support locations.

Shift forks have replaceable bronze inserts. The shift pattern is of the standard progression type with all shifts having
the same throw at the lever.

(Soft 4th)

CL457

(Short 4th)

CL450

(Straight 5-speed

A

CL 450 SERIES

ASSEMBLY INSTRUCTIONS

Unless otherwise specified:
Tighten all capscrews 20 to 25 lbs. ft. [27,2 - 33,8 N.m].

Use a Grade #2 Multi-Purpose Grease to retain needle
rollers in reverse idler gear bore during assembly.

Apply a thin coat of Loctite 510 Gasket Eliminator to the
O.D. of all oil seals and countershaft front bore plug
before assembly.

Hand-spin idler gear and countershaft assemblies after
each is installed on their bearings in trans. case. Both
must spin freely and smoothly.

Check all mainshaft constant-mesh gears to make sure
they rotate freely on mainshaft.

Fasteners that are removed and reused, apply Locktite
262 Adhesive/Sealant.

B

THE CLARK SYNCHRONIZER

AND HOW IT WORKS FOR YOU

The Clark split-pin synchronizer prevents the clashing of the gears and increase the speed of shifting.

In a conventional transmission which does not have synchronizers the absence of gear clashing is dependent entirely
on the skill of the truck driver. By double-clutching and split second timing of engine speeds with the gear shifting
movement, a driver can synchronize the speeds of the engaging gears and thereby prevent the damage to gears by
clashing when a fast shift. The splint-pin sychronzier performs the same function with or without the “double-clutching”
operating even though the driver does not accurately time his gear shifting movements. It also mechanically prevents
the driver from completing the shift to the point of gear engagement until the engaging gears have reached the same or
synchronous speeds. This is known as the blocking action of the synchronizer and it is this action that makes the oper­ation of shifting a transmission having synchronizers different from one which does not have synchronizers.

Upon shifting gears in these synchronized transmissions the first part of the gear shift lever movement brings the
blockers into contact. The blockers momentarily prevent further movement of the shift lever and the pressure exerted
by the driver to complete the movement, is transferred by the blockers to the synchronizer providing the force neces­sary to synchronize the gears being engaged. When the engaging gears have reached the same speed, the blockers
automatically disengage, permitting the gear shift lever movement to be completed. Therefore, to properly shift a syn­chronized transmission a steady and continuous pressure must be applied by the driver to the shift lever until the shift
is completed. Under normal conditions this action is instantaneous.

Sometimes difficulty is experienced in shifting a synchronizer when the vehicle is standing still. This is caused by the
fact that the disengagement of the blockers requires relative rotation and with the vehicle at rest and with the engine
clutch released, there may be at times, no relative rotation of the engaging gears. Under these conditions, the same con­tinuous pressure should be applied to the shift lever and at the same time, the clutch should be engaged slightly. This
will give sufficient rotation to unblock the synchronizer and allow the shift to be completed without difficulty.

C

RECOMMENDED LUBRICANTS FOR CLARK

MANUALLY SHIFTED TRANSMISSIONS

*Mil-L-2105C Extreme Pressure Lubricant (or API classification GL-5)
of the SAE viscosity recommended in the chart at the right is pre­ferred. All lubricants should be backed by the reputation of a well­know supplier. It is important to specify EP lubricants of the MIL-L­2105C type only, or of a API classification GL-5.

*Do not use extreme pressure lubricants other than MIL-L-2105C or
of a API classification GL-5.

Many EP lubricants contain highly-active chemical compounds that
have been formulated to perform satisfactorily in specific types of
applications. Severe corrosion, residual deposits, and inadequate
lubrication may result from improper application. Use of EP lubricants
other that MIL-L-2105C or of a API classification GL-5 may result in
failure and/or impaired operation.

DRAINING ECONOMY - The object in draining the transmission oil
periodically is to eliminate possible bearing surface abrasion and
attendant wear. Minute particles of metal, the product of normal wear
in service, are deposited in and circulate with the transmission oil. The
oil changes chemically, due to its repeated heating and cooling, also
the terrific churning it undergoes in the presence of air. It is desirable
to drain out this used oil after the first 1,000 miles (1609,0 Km) of
service (regardless of type of service). Subsequent drains should be

made every 24,000 miles (38616,0 Km) or six (6) months (whichever
comes first) for highway service, and every 8,000 to 10,000 miles [12872,0-16090,0 Km] or six (6) months (whichever
comes first) “on-off” highway and “pick-up and delivery” types of service. Do this only when the transmission is thor­oughly warm.

FLUSHING - After draining, flushing is desirable. Replace the drain plug and fill the transmission to the proper level with
a light flushing oil. Drive the transmission for a short period at fast idle in such a manner that the gears in the transmis­sion are rotating without load. This washes out the old oil clinging to the interior of the gear case, covers and shifter
rails. BE SURE TO DRAIN OUT ALL of the flushing oil before attempting to refill with new oil. This flushing procedure is
most important after first drain.

REFILL - First, removal all dirt around the filler plug, Then refill with new oil of a grade recommended for the existing
season and prevailing service. Fill to the bottom of the level testing plug positioned on the side of the transmission. DO
NOT OVERFILL, as the excess quantity will serve no useful purpose. If the oil level is too high, it will cause excessive oil
churning and high oil temperature and possible leakage.

INSPECTION - Oil level inspection should be made every 6,000 miles [9654,0 Km] which usually coincides with the
vehicle manufacturers chassis lube procedure. Always clean around filler plug before inspection. Add sufficient oil to
maintain correct level.

D

CLARK

E

CL450 -SERIES TRANSMISSION

ITEM DESCRIPTION QTY.

1 Control Cover Assembly ..........................................................1

2 Control Cover Screw Lockwasher ..........................................13

3 Control Cover Screw..............................................................13

4 Control Cover Gasket ..............................................................1

5 Mainshaft 2nd Gear..................................................................1

6 Mainshaft 2nd Gear Roller Bearing ..........................................1

7 Split Washer Retainer Ring......................................................1

8 Mainshaft 2nd Gear Split Washer.............................................2

9 Split Washer Lock Ball .............................................................1

10 Mainshaft 1st Gear .................................................................1

11 Mainshaft 1st Gear Bearing......................................................1

12 Mainshaft 1st & Reverse Shift Hub..........................................1

13 Mainshaft.................................................................................1

14 Mainshaft Reverse Gear Roller Bearing....................................1

15 Mainshaft Reverse Gear...........................................................1

16 Mainshaft Rear Bearing Thrust Washer ...................................1

17 Mainshaft Rear Bearing Cone...................................................1

18 2nd & 3rd Gear Shift Hub Sleeve .............................................1

19 2nd Gear Shift Hub Sleeve Retainer Ring.................................1

20 2nd & 3rd Gear Synchronizer Assembly ..................................1

21 3rd Gear Synchronizer Cup......................................................1

22 Mainshaft 3rd Gear Bearing ....................................................1

23 Mainshaft 3rd Gear..................................................................1

24 Mainshaft 3rd Gear Locating Washer Ball................................1

25 Mainshaft 3rd Gear Locating Washer.......................................1

26 3rd Gear Locating Washer Retaining Ring ...............................1

27 Mainshaft 4th Gear Bearing ....................................................1

28 Mainshaft 4th Gear ..................................................................1

29 4th & 5th Synchronizer Cup.....................................................1

30 4th & 5th Synchronizer Assembly............................................1

31 4th & 5th Synchronizer Cup.....................................................1

32 4th & 5th Shift Hub Sleeve ......................................................1

33 4th & 5th Shift Hub Thrust Bearing.........................................1

34 4th & 5th Shift Hub Thrust Bearing Race.................................1

35 Countershaft Front Bearing Cone.............................................1

36 Countershaft Drive Gear Retainer Ring ....................................1

37 Countershaft Drive Gear...........................................................1

38 Countershaft 4th Gear..............................................................1

39 Countershaft Gear Key.............................................................2

40 Countershaft 3rd Gear..............................................................1

41 Countershaft 2nd Gear.............................................................1

42 Countershaft............................................................................1

43 Countershaft Rear Bearing Cone..............................................1

44 Reverse Idler Gear Thrust Washer ...........................................1

45 Reverse Idler Gear ..................................................................1

ITEM DESCRIPTION QTY.

46 Reverse Idler Gear Bearing ....................................................26

47 Reverse Idler Gear Bearing Spacer...........................................1

48 Reverse Idler Gear Bearing ....................................................26

49 Reverse Idler Thrust Washer....................................................1

50 Mainshaft Rear Bearing Cap Nut..............................................4

51 Mainshaft Rear Bearing Cap Washer........................................4

52 Mainshaft Rear Bearing Cap .................................................... 1

53 Mainshaft Rear Bearing Cap Shim........................................ AR

54 Speedometer Driven Gear ......................................................1

55 Mainshaft Rear Bearing Cap Stud............................................4

56 Mainshaft Rear Bearing Cup....................................................1

57 Mainshaft Flange Nut............................................................... 1

58 Output Flange..........................................................................1

59 Mainshaft Rear Bearing Cap Oil Seal....................................... 1

60 Speedometer Drive Gear Tube Nut ..........................................1

61 Speedometer Driven Gear ....................................................... 1

62 Mainshaft Rear Bearing Cap Bolt............................................. 4

63 Mainshaft Rear Bearing Cap Bolt Washer................................ 4

64 Countershaft Rear Bearing Capscrew......................................4

65 Countershaft Rear Bearing Cap ............................................... 1

66 Countershaft Rear Bearing Cap Shim ................................... AR

67 Countershaft Rear Bearing Cup ...............................................1

68 Reverse Idler Shaft..................................................................1

69 Reverse Tab Lock Screw .........................................................1

70 Reverse Idler Shaft Lock ........................................................ 1

71 Mainshaft Roller Bearing Washer Retainer Ring......................1

72 Mainshaft Roller Bearing Washer............................................ 1

73 Mainshaft Roller Bearing ...................................................... 14

74 Main Drive Gear ......................................................................1

75 Main Drive Gear Bearing Cone ................................................1

76 Main Drive Gear Bearing Cup ................................................. 1

77 Main Drive Gear Bearing Cap Oil Seal......................................1

78 Main Drive Gear Bearing Cap Gasket....................................... 1

79 Main Drive Gear Bearing Cap...................................................1

80 Main Drive Gear Bearing Capscrews .......................................4

81 Transmission Case .................................................................. 1

82 Countershaft Front Bearing Cup.............................................. 1

83 Countershaft Front Bearing Race Locator Ring .......................1

84 Countershaft Front Bore Plug ..................................................1

85 Clutch Shaft Grease Fitting ...................................................... 2

86 Clutch Housing Cover .............................................................1

87 Clutch Housing Cover Screw Lockwasher............................... 2

88 Clutch Housing Cover Screw................................................... 2

89 Clutch Housing........................................................................1

90 Clutch Pedal Shaft Bushing ....................................................4

ITEM DESCRIPTION QTY.

91 Clutch Housing to Case Screw ................................................ 4

92 Clutch Housing to Case Screw Lockwasher ............................4

93 P.T.O. Cover Lockscrew.........................................................12

94 P.T.O. Cover Plate....................................................................2

95 P.T.O. Cover Plate Gasket.........................................................2

96 Magnetic Drain Plug................................................................1

97 Filter Plug................................................................................1

98 Name Plate Screw ...................................................................2

99 Name Plate..............................................................................1

AR = As Required

F

CLARK

F