Car Suspension Types
Believe it or not, the first suspension designs for automobiles were inspired by the horse-drawn carriages which preceded the first automobiles. These were basically beam axles, where a solid beam was attached via leaf springs to the vehicle chassis and the wheels were attached to the ends of the beams. Although solid beam axles worked well enough and are in fact still in use today in commercial and heavy-duty vehicles, ride quality requirements compelled car designers to look into suspension designs that provided improved ride and handling qualities. This is the era where designers used swing axles and trailing arm suspensions in an attempt to offer cars improved bump, steering and handling qualities. The Corvair is an example of a car that used swing axle suspension, while the VW Beetle was designed to use a trailing arm suspension.
One of the most significant suspension designs that were developed is the MacPherson strut, which was first used by Ford in the 1950s. It is very popular with manufacturers of mass-produced cars because of its simplicity and compactness. This simplicity also makes the MacPherson strut cheap to manufacture, and its compact design allows a drive axle to pass through the steering knuckle that the strut attaches to. It became a de facto standard for front wheel drive cars in the 70s and is still widely used today. Despite its advantages of being cheap to manufacture and compactness, the MacPherson strut was not well-suited to high-performance cars. Suspension engineers looking for better manipulation and handling developed the double A-arm, or dual wishbone, suspension, which allows a vehicle to generate maximum cornering force.
Up to today, the solid axle is used in the rear for very powerful cars. As with front suspensions, leaf springs were used for rear suspensions, and some mass-production cars used this rear layout until the early 80s. However, leaf springs have fallen out of favour and have been replaced by coil springs or struts. Locating the solid rear axle is accomplished by trailing links and lateral dominance rods that manipulation the movement of the axle during acceleration and braking. There are other layouts for locating and controlling the so called live axle, but the 4-link is the most common and popular layout in use for cars still using a solid rear axle. However, very few, if any, of today's cars use a solid axle for the rear. Independent rear suspensions are commonplace nowadays, whether a car is front wheel drive, rear wheel drive or all wheel drive. Front wheel drive cars usually employ a variation of their front suspension, modified for use in the back end of the car. Generally, these are either a McPherson style suspension or an A-arm setup. Rear wheel drive cars, on the other hand, normally use different front and rear suspensions. What is prevalent is the use of multi-link rear suspensions to provide a very comfortable ride without degrading handling quality. With all-wheel drive cars, the prevalent suspensions in use are the McPherson strut or unequal length double A-arm. All-wheel drive cars are generally higher-performance cars and their suspension tuning is favoured toward handling over ride quality.