Rear Suspension

COMPONENT LOCATION








INTRODUCTION
The rear suspension is a double wishbone design which is attached to a rear crossbeam. The crossbeam is attached to the vehicle body with 4 long bolts which pass through bushes located in the crossbeam.

The rear suspension on each side comprises:

^ Upper control arm
^ Lower control arm
^ Toe-link
^ Wheel knuckle and hub assembly
^ Stabilizer bar
^ Spring and damper module.

UPPER CONTROL ARM








The cast aluminum upper control arm is a wishbone design with 3 mounting points. Two bushed mountings locate in brackets on the crossbeam. The outer end has a ball joint which mates with the wheel knuckle.

LOWER CONTROL ARM








The cast aluminum lower control arm is a wishbone design with 3 bushed mounting points. Two bushes locate between brackets on the crossbeam and the outer bush locates in the wheel knuckle.

The rear of the control arm has mounting points for the damper and the stabilizer link.

TOE-LINK








The toe-link is located between the wheel knuckle and brackets on the rear crossbeam.

The toe-link comprises an inner rod with integral ball joint. The inner ball joint has a threaded spigot which locates in a bracket on the crossbeam and is secured with a washer and locknut. The rod has an internal thread which accepts the outer rod.

The outer rod has a ball joint at its outer end which is located between 2 brackets on the wheel knuckle, and is secured with a bolt and locknut.

The length of the toe-link can be adjusted by rotating the inner and outer rods. This allows for adjustment of the toe angle for the rear wheel. Once set the inner and outer rods can be locked in position by tightening a locknut against the inner rod.

WHEEL KNUCKLE








The wheel knuckle is an aluminum casting which provides for the attachment of the upper and lower control arms and the toe-link. The wheel knuckle also provides the mounting locations for the wheel hub and bearing assembly, the wheel speed sensor and the brake caliper and brake dust shield which is secured with 3 rivets.

The wheel hub assembly includes the wheel bearing. The hub assembly is a non-serviceable component and requires replacement as a complete assembly. The wheel hub is secured to the knuckle with 4 bolts.

STABILIZER BAR








The stabilizer bar is attached to the top of the crossbeam with 2 bushes and mounting brackets. The brackets are secured to the crossbeam with bolts and caged nuts. The stabilizer bar has crimped, 'anti-shuffle' collars pressed in position on the inside edges of the bushes. The collars prevent sideways movement of the stabilizer bar.

The stabilizer bar is manufactured from manganese steel bar and is available in 2 diameters, dependant on the vehicle model. Each type of stabilizer bar has a different torsional rate and is also color coded for identification.

Stabilizer Bar Diameters





Each end of the stabilizer bar curves rearward to attach to a ball joint on each stabilizer link. Each link is attached via a second ball joint to a cast bracket on the lower control arm which is secured with a locknut. The links allow the stabilizer bar to move with the wheel travel providing maximum effectiveness.

The stabilizer bar is attached to the forward face of the chassis front subframe. The stabilizer bar is attached to the subframe with 2 rubber bushes. Pressed steel brackets locate over the bushes and are attached to the cross member with bolts screwed into threaded locations in the subframe.

SPRING AND DAMPER MODULE








The spring and damper modules are attached to cast brackets on the lower control arms and to the rear floor side member assemblies via the 4 studs in the top plate. Similar to the front suspension, two variants are available; passive and active. The active spring and damper assemblies employ the CATS active suspension system.

Different combinations of springs and dampers are available depending on the vehicle model. The damper and spring assemblies are similar in their construction with the CATS adaptive damper having a solenoid operated valve installed in the damper body.

The dampers are a monotube design with a spring seat welded onto the damper tube. The lower end of the damper has a bushed mounting which locates in the lower control arm and is secured with a bolt.

The damper functions by restricting the flow of hydraulic fluid through internal galleries in the damper piston, providing damping of undulations in the road surface. The CATS damper has a solenoid operated valve which further restricts the flow of hydraulic fluid, providing a stiffer damping characteristic for the damper and improving vehicle handling. The solenoid is computer controlled and can switch between soft and hard damping settings depending on driving style and vehicle speed.

The damper piston is connected to a damper rod which is sealed at its exit point from the damper body. The threaded outer end of the damper rod locates through a hole in the top mount. A self locking nut secures the top mount to the damper rod. The damper rod on CATS dampers have an electrical connector on the outer end of the damper rod.

The damper rod is fitted with a spring aid which prevents the top mount making contact with the top of the damper body during full suspension compression and also assists with the suspension tune.

The spring rate of the coil springs can differ between models and are color coded for identification. The coil spring locates on a spring packer and a lower spring seat which is integral with the damper body. The spring locates in an upper spring seat which is located on the underside of the top mount.

The top mount has 4 studs which locate through mating holes in the vehicle rear floor side member and are secured with self locking nuts.