TOPIC 1. DRIVE AXLE - TM-10-3930-644-14-P0104

TM 10-3930-644-14&P

DRIVE AXLE

TOPIC 1. DRIVE AXLE

A. DESCRIPTION

the axle shafts serve only to drive the wheels.

The drive unit is a double reduction, internal gear drive

The differential is of the bevel gear and pinion type with

within wheel, and a spiral bevel in axle housing. The

the final drive reduction through the axle shafts

drive wheels are mounted on an axle housing spindle by

(jackshaft) and bull gears (Figure 2), setting each drive

two opposed tapered roller bearings, locked in correct

wheel into motion. In order to hold the differential

adjustment by a washer, a castellated nut and cotter pin.

assembly rigidly in place in the housing, it is mounted on

The weight of the truck is carried by the axle housing,

two studs and then held firmly in position by self-locking

and through the wheels (See Figure 1); therefore, the

cap screws.

The axle shafts (jackshaft) are splined to the differential

side gears at one end and mesh with the bull gear in the

drive wheel at the opposite end. The axle shaft teeth are

crown-shaved to ensure proper meshing with the bull

gear. The axle shafts rotate at the drive wheel end in

two opposed tapered roller bearings, which are locked in

place on the shafts by a sleeve type nut and spider lock

ring. The assembly is locked in position in the axle

housing by a bearing cap and capscrews.

The bull gear is correctly located in the drive wheel by

roll pins and is bolted into the wheel from the outside so

that tightness can be checked periodically without the

necessity of removing the wheel.

Figure 1. Drive Axle Assembly (Typical)

Figure 2. Drive Unit Components (Typical)

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