Control Arm: Description and Operation

Wishbone Assemblies
Both upper and lower wishbone assemblies are attached to the crossbeam by fulcrum bolts. The upper wishbone is a single-piece steel forging, which is fitted with a press-fit ball joint, and two slipflex bushes to each arm. A single fulcrum bolt attaches the upper wishbone to the crossbeam. Shims installed with the upper fulcrum bolt are used to adjust the caster setting.
The wide-base lower wishbone comprises two steel forged arms bolted together. The front wishbone arm is tapped to accept the two bolts which secure the two wishbone arms together. Additionally the two bolts also secure the shock absorber mounting brackets to the wishbone. Each lower wishbone arm is fitted with a metal-to-rubber bonded fulcrum bush which is attached to the crossbeam by an independent fulcrum bolt. The rear wishbone arm has a press fit ball joint installed.
The camber setting is adjusted by rotating the lower-wishbone rear fulcrum bolt, which has an eccentric shaft. However, in some markets the eccentric bolt is not fitted and the original fulcrum bolt has to be substituted with an eccentric bolt to enable adjustment. The eccentric bolt is supplied by Jaguar Cars Ltd.