RAM A. 2D2823 - Caterpillar

Illustration 1 g00727007
Typical Example of the Front Axle and the Rear Axle Components (1) Axle shaft (2) Universal joint (3) Steering case (4) Hub (5) Bolt (6) Ring gear (7) Planet gear (8) Gear carrier (9) Pinion (10) Gear (11) Roller bearingThe final drives provide the final gear reduction to the road wheels. The components that are shown in Illustration 1 are located at each side of the axle.The inner end of axle shaft (1) is splined to the side gear in the differential. The outer end of the axle shaft is splined to universal joint (2) .The axle shaft is splined to pinion (9). Planet gears (7) are pinned to gear carrier (8). The planet gears are in constant mesh with the pinion and ring gear (6) .The ring gear is held stationary by gear (10) which is bolted to steering case (3). Hub (4) is supported on the steering case by roller bearings (11) which are retained by gear (10) .The universal joint and the axle shaft rotate the pinion which then rotates the planet gears. Since the ring gear is held stationary, the planet gears rotate inside the ring gear in order to turn the gear carrier in the same direction as the pinion. Since the distance that is travelled by the gears is relative to the size of the gears, a gear reduction is provided between the speed of the pinion and the gear carrier which turns the hub.