Differential Assembly: Description and Operation

Rear Drive Axle Description and Operation





The vehicle is powered by either the LY9 V6 2.6 liter or the L81 V6 3.0 liter. Motion is transferred from the engine crankshaft/flywheel through the driveline support, propeller shaft, assembly to either the 5L40-E (M82) automatic transmission or the Getrag (M35) 5 speed manual transmission. The splined output shaft of the transmission drives the pinion, which in turn, rotates the ring gear and differential case assembly. The differential distributes torque/power to the rear wheels via individual axle shaft assemblies.

The differential housing, side cover and pinion housing are constructed of cast aluminum. The internal components incorporate a hypoid gear set, ring and pinion, carrier assembly and pinion housing assembly. The pinion is supported in a pinion housing by tapered roller bearings. The pinion is positioned rearward of the ring gear centerline. All models have a 7 5/8 inch ring gear. Each ring gear has specific setup dimensions, A1 and A2 values, stamped onto the side area of the gear. The A1 and A2 values are unique to each ring gear/ pinion and are determined during the manufacturers gear/pinion noise and vibration setup and testing. Pinion position, ring gear position and carrier bearing preload are determined by shimming procedures.

The differential assembly is available in three gear ratios. The 3.42 ratio axle is used in all automatic transmission applications. The 3.73 ratio axle is standard equipment for automatic/manual transmission applications and the 3.91 ratio axle is used in manual applications only.