Differential Assembly: Description and Operation

EXC. CORVETTE
In these rear axles, the rear axle housing and differential carrier are cast into an integral assembly. The drive pinion assembly is mounted in two opposed tapered roller bearings. The pinion bearings are preloaded by a spacer behind the front bearing. The pinion is positioned by a washer between the head of the pinion and the rear bearing.
The differential is supported in the carrier by two tapered roller side bearings. These bearings are preloaded by spacers located between the bearings and carrier housing. The differential assembly is positioned for proper ring gear and pinion backlash by varying these spacers. The differential case houses two side gears in mesh with two pinions mounted on a pinion shaft which is held in place by a lock pin. The side gears and pinions are backed by thrust washers.
A limited slip rear axle, available on most models, uses disc or cone type clutches which are splined to the side gears to ``lock'' the axle shafts to the case, or in effect to each other. Therefore, if one drive wheel is on a slippery surface, the other wheel must develop more torque than on a standard type differential before the differential case will allow wheel spin. However, axle shaft torques produced during cornering are sufficient to overcome the clutch action, allowing axles to rotate at different speeds.