We continue the topic from last week with the different types of suspension systems found in vehicles today. 

Types of suspension

The four wheels of a car work together as two independent systems – the front wheels connected by the front axle and the back wheels connected by the rear axle. What it means is that a car can and usually has a different type of suspension on the front and back. Suspension systems can also be grouped into dependent and independent systems.

Front suspension

Dependent systems
As the name suggests, the front wheels can move independently. This type of suspension delivers the best ride characteristics and is commonly used in passenger cars and minivans.

Independent systems
When a car’s wheel goes over a bump, the spring absorbs that additional load and keeps the road shock from reaching the chassis. This ensures that the tyre maintains contact with the road. There are three types of springs:

The most widely used front suspension system is the MacPherson strut. The strut usually carries both the coil spring on which the body is suspended, and the shock absorber, which is usually in the form of a cartridge mounted within the strut. The strut also has a steering arm built in. Although it is relatively easy to assemble and cheap to manufacture, it tends to transmit more noise and vibration from the road, compared with double wishbone systems.

The double-wishbone suspension, also known as an A-arm suspension, is another type of front independent suspension. While there are different configurations, this design typically uses two wishbone-shaped arms to locate the wheel.

Each wishbone has a shock absorber and a coil spring to absorb vibrations and has two mounting positions at the frame and at the wheel. Double-wishbone suspensions allow more control over the camber angle of the wheel, which describes the degree to which the wheels tilt in and out. They help minimise vehicle sway and provide for a more consistent steering feel. 

Rear suspension

Rear suspensions, in general, are much simpler than front suspensions since their main job is to support the rear of the vehicle and provide some sort of suspension control. There are three basic types of rear suspension.

Independent rear suspension systems may be found on rear, front, and four-wheel drive vehicles. They utilise control arms which allow one wheel to move separately from the other.

Semi-independent systems are often found on front wheel drive vehicles. These systems utilise a cross member, which connects to two trailing arms.

Dependent systems are usually found on rear and four-wheel drive vehicles. These systems consist of leaf or coil springs used in conjunction with the live axle, which is the differential axle, wheel bearings and brakes operating as one unit.