The rear suspension has two primary purposes:
| • | Isolate the driver from irregularities in the road surface. |
| • | Define the ride and handling characteristics of the vehicle. |
The rear suspension absorbs the impact of the tires travelling over irregular road surfaces and dissipates this energy throughout the suspension system. This process isolates the vehicle occupants from the road surface. The rate at which the suspension dissipates the energy and the amount of energy that is absorbed is how the suspension defines the vehicle's ride characteristics. Ride characteristics are designed into the suspension system and are not adjustable. The ride characteristics are mentioned in this description in order to aid in the understanding of the functions of the suspension system. The suspension system must allow for the vertical movement of the tire and wheel assembly as the vehicle travels over irregular road surfaces while maintaining the tire's relationship to the road.
The rear suspension of this vehicle is a coil sprung rigid axle with 5 links. The 2 upper control arms control the longitudinal movement and the rotational movement of the axle. The 2 lower control arms also control the longitudinal movement and the rotational movement of the axle. The rear axle tie rod controls the lateral axle movement. The control arms and the tie rod retain the axle to the frame with semi-rigid bushings. The 5 links allow the axle to move up and down as the vehicle travels over bumps. This control of axle movement defines the vehicle's handling characteristics in turns.
The up and down motion of the axle is absorbed predominantly by the coil spring. This spring is retained under tension between the axle and the frame. The 2 shock absorbers dampen the oscillations of the coil spring. A shock absorber is a basic hydraulic cylinder. A shock absorber is filled with oil and has a moveable shaft that connects to a piston inside the strut. Valves inside the shock absorber offer resistance to oil flow and consequently inhibit rapid movement of the piston and shaft. This control of vertical axle movement defines the vehicle's ride characteristics as the vehicle travels over bumps.
