Vehicle Suspension Types and How it Works

When it comes to vehicle suspension, there are several components that you should know of as suspensions for each car varies. 

Suspensions in a rear-wheel drive varies from a front-wheel car, suspensions from small cars varies from SUV’s and trucks. However, they all provide the same purpose – to attach the wheels to the chassis and provide a comfortable ride. 

So in this short blog post, I will discuss several suspension types, components and how they work on your car. Lets get started!

Vehicle Suspension Types

As mentioned above, the purpose of suspensions is to attach the wheels of your car to the chassis while providing comfort and less bumpy ride as the suspensions move up and down through springs and dampers. 

Suspensions are designed to help the wheels to pivot and rotate freely as needed. As such, front wheels should pivot through their steering swivels so the wheels can go left or right. The driven wheels (the wheels that has traction or power) whether front or rear-wheel drive, must also rotate freely through drive shafts.

Car suspension is a system that is composed of tires, tire air, springs, shock absorbers or dampers, rods, axle, frame, steering arm, wishbones and many other linkages that connects the vehicle to the wheels.

But I am not going to discuss all the tiny details here but only the basic major parts of common car suspension types that are used in todays vehicles. And lets start with non-independent suspension.

Non-Independent Suspension

Non-independent (or also known as dependent) suspension means that the left and right wheels share a single but very solid axle. An axle is a solid metal tube that contains both drive shafts (half shafts) and the differential gears. 

This type of suspension is still common in modern vehicles today especially with SUV’s and trucks. 

Some all-wheel or 4×4 vehicles do have the same live axle at the front as shown from the image below. Vehicles such as vans and some trucks have a rigid beam called “dead axle”, while some front-wheel drive cars use dead rear axle. 

A rigid axle use springs and linkages like bars to help prevent sideways movement. The common complaint about non-independent suspension is the jarring and shaking are felt across the entire rear axle if either wheel hits a bump. It is also not good in preventing body roll.

Independent Suspension

Unlike dependent suspension where the left and right wheels share one solid axle, independent suspension means each wheels are independently attached to the body or subframe.

This means that a variety of spring combinations are used which results to a better ride quality as shaking or jarring is significantly lessened.

Let me give you the various types of independent car suspension that are widely used in modern cars today. 

Double Wishbones

This type of car suspension is used widely at the front of big vehicles such as trucks and SUVs. They are called “wishbones” as they are designed like the wishbone found in chickens and other poultry products. Other common names for this suspension are A-arm, upper and lower arm.

Sedans do have one upper wishbone suspension at the front so they aren’t exactly called a double wishbone suspension. But big trucks uses two wishbone arms (upper and lower arm) that are mounted at the frame and the other at the wheel. 

Wishbones helps keep the wheel upright as it hits bumps and pot holes on the road. 

MacPherson Strut

This type is commonly used as a front independent car suspension system as it’s effective and quite a simple system. However, some cars do use MacPherson strut at both front and rear wheels too. 

So what are the components of this type of suspension? It is composed of a shock absorber or damper and a coil spring, into a single strut, to provide a more compact, lighter but smooth suspension system.

The wheel hub (where the wheel is directly attached to) is fixed rigidly to an upright, telescopic, tubular strut. On the front wheels, the whole strut swivels which allows swift steering. This is the reason why front-wheel drive vehicles use this type of suspension. 

Trailing Arm, Leading Arm and Swing Axles

Other car suspension systems includes a trailing arm, a leading arm and swing axles. A trailing arm is connected directly to the wheel hub at one end, and extends forward to a pivot on the frame. The arm is a V shape that pivots on either side or with the inner pivot slightly behind the front one, which is also called a semi-trailing arm.

A leading arm on the other hand, is only used at the front and is the opposite of the trailing arm as the wheel in front of the pivot. Swing axles can be located either at the front or rear wheels. 

Anti-Roll Bars, Multi-Link and Independent Rear Suspensions

Multi-link suspension is a car suspension system that contains one or more longitudinal arms, and one or more lateral arms, that are all angled in any direction which allows for a better ride and handling. Multi-link car suspensions are commonly used on performance cars.

Independent rear suspension systems are found on the rear axles, which are simpler as the wheels are not attached to the steering rack. 

Lastly, anti-roll bar’s role is to prevent the car from leaning over on corners or from complete rolling. These bars are often used at the front, but mid-size to large-size SUV’s and trucks do have anti-roll bars on both the front and back. 

Anti-roll bar uses a solid metal bar acting like a torsion bar, crossing through the two pivots on opposite sides of the car frame. This bar is connected to each sides of the wheel through end linkages with rubber bushes. 

It works when you drive on corners by preventing rolling or too much leaning on one side. As one wheel moves up, the bar pulls up one end of the bar and the other end pulls up the other wheel, which keeps the car level during cornering.

Conclusion

There you have it! Now you know how your car suspension works! Watch my video below and learn how suspension works on both cars and SUVs. The video has English subtitle, so enjoy watching!

Until next time guys!

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