DRIVE UNIT SERVICE - TM-10-3930-644-14-P0306

TM 10-3930-644-14&P

B. DRIVE UNIT SERVICE

Jackshafts and bearings, bull gears and wheel bearings

should be inspected and serviced at periodic intervals.

All parts should be checked for any possible damage or

excessive wear. The Level of the oil in the differential

housing should be checked. and also changed when

specified.

The housing breathers should be kept clean and open to

prevent any pressure from building up in the unit.

NOTE

Refer to the LUBRICATION AND

SERVICE

GUIDE

for

specific

instructions regarding lubrication of

the drive unit.

The drive unit can be removed as an assembly. if

desired. It will be necessary to remove the mast

assembly in order to remove the drive unit.

The

following procedure is recommended for drive unit

removal:

Figure 3. Drive Unit Removal

1. Removal

2. Installation

a. After the mast has been removed (see

MAST REMOVAL), disconnect the man

a. To replace the drive unit assembly,

hydraulic brake line at the junction block

carefully raise the truck body high enough

located on the differential housing.

with hoisting chain to position drive unit

Disconnect the hydraulic Lines, the

under front end at dowel pain location.

leakage return line, or any other lines

which are attached to the drive unit

housing.

b. Lower truck frame until It is securely

supported at the mounting pads and insert

b. Disconnect the emergency brake cable by

all mounting bolts and capscrews

removing the clevis pin from the parking

previously removed.

brake actuating lever.

c. Connect universal joint and ensure that

c. Disconnect the universal joint (see U-

drive shaft coupling is properly aligned.

JOINTS).

leaving slip joint in the

transmission.

(Refer to TRANSMISSION for proper

alignment procedure.) d.

Connect the

d. See Figure 3 and attach hoist chain hooks

emergency brake cable by replacing the

in the tit cylinder holes min the front plate.

clevis pin at actuating level.

Pull chain snug to take the weight of the

truck off drive axle.

e. Securely tighten all mounting hardware

e. Remove all mounting bolts and capscrews

and hose connections and bleed the

from mounting pads.

hydraulic brake system.

(Refer to

HYDRAULIC BRAKE Section for proper

f. Raise the truck away from the drive unit

procedure.)

and remove drive unit from under the truck

frame. It may be necessary to apply

f. Replace the mast assembly.

(Refer to

pressure at the mounting pads in order to

MAST ASSEMBLY Section.)

free the drive unit from the truck, because

of the tight fit of the dowel pins in the

mounting pads.

NOTE

For service instructions on the drive

unit assembly. refer to DRIVE UNIT

DISASSEMBLY.

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