SAAB WIS ONLINE

Limited Slip Differential Description and Operation

Limited Slip Differential Description and Operation

The limited slip differential clutch is bolted with 6 bolts to the left-hand side of the differential carrier. Their relative position is governed by 2 guide pins and a flange on the final drive gear.

Its function is to fully or partly lock the left-hand drive shaft to the differential housing. When this takes place wheel torque can be distributed between the rear wheels.

The limited slip differential clutch is a disc type, and it is electro-hydraulically controlled by the rear drive control module (RDCM) via a pressure control valve which is fitted on the limited slip differential clutch housing. The disc pack assembly consists of a hub, smooth steel driven plates with friction material, clutch cage, thrust bearing and journal bearing. The function of the disc pack is to variably distribute the torque between the rear wheels. It contains 9 driven plates which are attached to the hub. They are produced in steel and are smooth. Between the smooth steel driven plates are 8 steel discs equipped with friction material.

The disc pack is compressed by means of an operating piston. On the rear of the piston a variable oil pressure (0-30 bar, 0-3000 kPa) acts via the pressure control valve which is controlled by the RDCM.

For cooling and lubrication of the disc pack the hub is equipped with 3 longitudinal oil ducts. They are supplied with oil from a chamber in connection with differential carrier. The oil is led through the ducts to the center of the disc pack and is thrown out through the driven plates when they rotate.