Rear Suspension
Rear Suspension
Rear Suspension Components
The independent rear suspension uses co-axial spring and damper units, an "A" frame, wishbone tie, pendulum assembly, wide mounting frame, monostrut and cast wishbones. Positive location of the suspension is provided by the "A" frame, wide mounting bracket and monostrut. Each wishbone inner is pivoted on a fulcrum bolt which passes through the wishbone tie and pendulum assembly.
The wishbone tie and pendulum assemblies are installed at the front and rear of the final drive housing. The monostrut is also attached to wishbone tie assembly and two further tie rods are installed between the front of the "A" frame and the top of the final drive housing.
The outer end of the wishbone is bolted to the hub carrier assembly using a pivot bolt, allowing for toe-in adjustment. When the pivot bolt is correctly seated in a groove on the wishbone arm, it has small clearance at the sides but full clearance at the top and bottom. Rotation of the bolt, with the eccentric constrained between vertical faces, causes the bolt shank to be moved in the horizontal plane, thus moving the hub carrier and effecting wheel alignment adjustment.
The axle-shaft acts as the the upper wishbone and the hub carrier as a vertical link.
A snubber is installed above the hub carrier to prevent the carrier contacting the vehicle body.
The suspension spring is co-axial with the damper unit and is installed between the wishbone integral spring seat and the upper spring seat mounted on the vehicle body. The damper lower end is attached to the wishbone by a bolt which forms the damper lower pivot.
A stabilizer bar is mounted at the rear of the wishbone tie assembly and its outer ends are connected to the wishbones by short links.
As the road wheel rises, the movement is transmitted through the hub carrier assembly to the wishbone and axle-shaft, which also rise. As the wishbone rises, it causes the suspension spring to be compressed and the damper to move through part of its travel. The spring absorbs the shock and the damper damps any unwanted spring frequencies.
When cornering, weight is transferred to the outer wheel with a natural tendency for the inner wheel to lift. The stabilizer bar helps to minimize this by transferring some of the apparent rise of the outer wheel to the inner wheel through the links to the wishbones, helping to provide a more level ride. Adaptive damping may also be specified as an option.
Description
The independent rear suspension incorporates co-axial spring and shock absorber units, a subframe, wishbone tie, pendulum assembly, mounting bracket, monostrut, cast wishbones and hub carriers. The suspension assembly is positively located by the subframe, mounting bracket and monostrut.
- Each wishbone pivots on a fulcrum bolt which locates in the wishbone tie and pendulum assembly.
- The wishbone tie and pendulum assemblies are respectively installed at the front and rear of the final drive housing.
- The monostrut is secured to the wishbone tie assembly.
- Two tie rods are installed between the front of the subframe and the top of the final drive housing.
- The outer extremity of each wishbone is secured to its respective hub carrier assembly by a fulcrum bolt.
Each fulcrum bolt head incorporates an eccentric circular flange which locates in a groove in the front face of the wishbone arm. Rotation of the fulcrum bolt results in horizontal movement of the bolt shank in an elongated hole in the rear of the wishbone arm. This action achieves corresponding movement of the hub carrier, facilitating adjustment of road wheel toe-in.
- Each road spring is located between the wishbone integral spring seat and the body suspension turret.
- Each shock absorber is installed co-axially within the road spring.
- The lower end of each shock absorber is secured to the wishbone by a bolt which also functions as a pivot.
- Adaptive damping is available as an option.
- A rear stabilizer bar is installed on Supercharged and Sport Suspension models. Mounted at the rear of the wishbone tie assembly, the stabilizer bar is connected to the wishbone by short links.
Operation
As each road wheel rises, movement is transmitted through the hub carrier assembly to the wishbone and axle shaft. The corresponding rise of the wishbone compresses the road spring and partially telescopes the shock absorber. During this action, the spring absorbs resulting shocks and the shock absorber minimizes spring oscillation.
During cornering, vehicle weight is transferred to the outer road wheel with a resulting tendency for the inner wheel to lift. On Supercharged and Sport Suspension vehicles, a rear stabilizer bar assists in minimizing this tendency by transferring a proportion of potential lift of the inner wheel to the outer wheel. This results in enhanced body stability with improved cornering capabilities.
Enhanced Handling Pack
An optional enhanced handling pack, which can be either factory or dealer installed, is available for XK coupe vehicles fitted with adaptive damping only. If the handling pack is installed the high performance Brembo brakes and special wheels must also be installed. The handling packs consist of special:
- Coil springs.
- Shock absorbers.
- Adaptive Damping Control Module (ADCM)
- Increased diameter, front stabilizer bar.
- Reduced diameter, rear stabilizer bar.
- Steering rack.
- Power steering control module.