Differential Assembly: Description and Operation

CORVETTE
These models are equipped with Positraction differentials. In this axle, the drive pinion is mounted in two tapered roller bearings that are preloaded by a spacer. The pinion is positioned by a shim located between the head of the drive pinion and the rear pinion bearing. The front bearing is held in place by a large washer and a locking pinion nut. The differential is supported in the carrier by two tapered roller side bearings. The differential side bearings are preloaded by shims between the bearings and carrier housing. The differential assembly is positioned for proper ring gear and pinion backlash by varying the position and thickness of these shims. The ring gear is bolted to the case. The case houses two side gears in mesh with two pinions mounted on a pinion shaft which is held in place by a lock screw. The side gears are backed by thrust washers. The differential side gears drive two splined yokes which are retained by snap rings located on the yoke splined end. The yokes are supported on caged needle bearings pressed into the carrier, adjacent to the differential bearings. A lip seal, pressed into the carrier outboard of the bearing, prevents oil leakage and dirt entry.