What is a car suspension?

12 minute read Published on Dec 8, 2023 by BrokerLink Communications

A car mechanic hand tightens the suspension of an elevated vehicle

If you’re a vehicle owner , then it's important to understand how your car works. One of the most important components of a car is the suspension, so that’s exactly what we’re discussing today.

Keep reading to learn more about what a car suspension does, the different types of car suspensions, and the different parts that make up your vehicle’s suspension.

Vehicle suspensions

First thing’s first, what is a suspension? A suspension is the part of a motor vehicle that reduces vehicle sway as it drives through various road conditions. More specifically, the suspension cushions the blow that the cabin would otherwise feel as the car moves over external forces, which include everything from speed bumps and potholes to small stones or gravel.

In essence, the suspension negates these external forces. Thus, your car’s suspension is what you can thank for the stable handling and comfortable ride that your vehicle offers. Without a car suspension, driving a car would be extremely uncomfortable and dangerous.

What does a car suspension do?

The main purpose of a car suspension is to ensure the stability of your car at all times. The suspension does this by absorbing the bumps of the road, whether they be potholes, rocks, speed bumps, etc.

It is the suspension that prevents the drivers, passengers, and car cabin from feeling the forces of these bumps. It is also the car suspension that keeps the car stable while driving. Whether you’re driving at low speeds or high speeds, the suspension will adapt and extend to make sure that the tires remain in contact with the road at all times.

Without car suspension, your vehicle would have no way of reducing the vehicle sway and absorbing these bumps, which could wreak havoc on the vehicle. For example, driving a car with no suspension could cause the tires to lose contact with the road, which in turn, could cause the driver to lose complete control of the vehicle. But with car suspension, the car is cushioned and remains stable.

How does a car suspension work?

A suspension system is made up of several key components, including the springs, shock absorbers, and struts. But how do these parts work together to make your car more stable to drive? To put it simply, a car suspension works according to the principle of force dissipation.

The suspension converts the force into heat, which allows the impact that the force has on the car to be significantly minimized. We go into greater detail about each of these components below.

Types of car suspensions

You might think there is only one type of car suspension, but you thought wrong. Due to major advancements in the automotive industry, automakers have come up with multiple types of car suspensions broadly divided into two categories: non-independent and independent car suspensions. We provide an overview of the different types below:

Non-independent car suspensions

Non-independent car suspensions are less popular nowadays and are not typically used for new cars. That said, they can still be seen in some trucks and SUVs. This type of vehicle suspension uses a solid bar known as a rigid axle that connects the left wheels with the right wheels with the help of springs and shock absorbers:

Leaf spring car suspensions

Leaf spring car suspensions are a type of non-independent car suspension. With this type of suspension, the leaf springs, which are made out of multiple plates bound together by rebound clips, are connected to a solid axle. Leaf spring car suspensions are relatively cheap to manufacture and have a reputation for withstanding a lot of weight. Today, they are mostly used in heavy vehicles, like buses and trucks.

Trailing arm car suspensions

Trailing arm car suspensions help to control the vehicle so that it absorbs forces on all sides. How this type of suspension works is that trailing control arms are attached to the axle and the vehicle’s chassis. They function similarly to leaf springs in that they negate the external forces that the axle bears the brunt of.

Independent car suspensions

Independent car suspensions are the other main type of car suspension. They are currently the most popular type and are more complex in their construction. Independent car suspensions function like this: the left and right wheels move independently of one another using an arrangement of springs and shock absorbers. These arrangements vary depending on the type of independent car suspension being engaged:

MacPherson strut car suspensions

MacPherson strut car suspensions are one of the most common types of car suspensions seen today. They are lightweight, compact, and relatively inexpensive due to their simple construction. They use two main components: coil springs and shock absorbers. They are used in many types of passenger cars, with the exception of sports cars and cars with wider wheels.

Double-wishbone car suspensions

Double-wishbone car suspensions are a second type of independent car suspension. They are often found in luxury vehicles and they operate using two wishbone-shaped arms that hold the wheel in place. The wishbone arms are mounted between the frame and the wheel and then the coil springs absorb energy. Since double-wishbone car suspensions are fairly complex in their construction, they are more expensive to manufacture and thus are mainly used in high-end cars.

Multi-link car suspensions

Multi-link car suspensions are a newer version of the double-wishbone car suspension. It uses three or more lateral arms and at least one vertical arm, all of which can be angled in the direction of your choice. This leads to improved ride comfort, stability, and handling. Given how advanced multi-link suspensions are, they are currently used in high-end cars.

Air ride suspensions

Finally, air ride suspensions are an extremely advanced type of independent car suspension that is chiefly found in luxury vehicles and sometimes larger work vehicles, such as diesel trucks or 18 wheelers. This type of suspension functions by replacing traditional coil springs with air springs, which are made out of rubber and inflated air.

Additionally, the suspension features an air compressor, electronic controls, and sensors. One of the main benefits of air car suspensions is that they can be adjusted according to the road and load limit of the vehicle. Due to how advanced this system is, it is expensive to manufacture, which is what makes it less common.

What parts make up the car suspension?

As mentioned previously, there are a few main components that make up a car suspension. No matter what type of suspension is found in your car, you can generally expect the suspension to be made up of the following: springs, shock absorbers or dampers, struts, and an anti-roll bar:

Springs

Springs are a key component of any type of car suspension system. The spring in your car’s suspension will compress or extend depending on the force that is applied. In essence, the role of the springs is to store and rebound energy that is generated when your vehicle drives over a rock, pothole, or bump.

Generally speaking, when you are driving on a flat or paved road, the springs compress due to the weight of the vehicle. In contrast, when you are driving over a dip in the road, the springs temporarily extend to make sure that the tires remain in contact with the surface of the road.

The three main types of springs are coil springs, leaf springs, and air springs. Air springs are the least common, used mainly in high-end, luxury vehicles that use air car suspensions. Coil springs are the most popular and are found on most cars regardless of value. Finally, there are leaf springs which are primarily used in older cars, such as used vehicles, classic cars, or heavy-duty vehicles, like trucks and buses.

It’s worth noting that while springs are an integral part of any car suspension system, they alone cannot facilitate a stable and smooth driving experience. Rather, they need to work in partnership with other components of the suspension, like the shock absorbers, to work effectively.

Shock absorbers

The shock absorbers, also known as dampers, are the next important part of any car suspension system. Absorbers are fluid or gas-filled reservoirs that are encased in a tube. They are located between the vehicle’s frame and its wheels. Typically, the upper mount of the absorber is attached to the vehicle’s frame and the lower mount is connected to its axle. As mentioned above, the springs and the shock absorbers work together.

If a wheel goes over a dip in the road, the springs extend. When this happens, the energy stored in the spring is transferred to the shock absorber. From there, the energy is distributed to the piston rod and into the piston, which moves through the oil.

There are multiple types of shock absorbers, including single-tube, twin-tube, and gas-filled dampers. However, no matter which your car uses, the result is the same, which is to absorb energy and cushion the feel of any bumps or dips in the road.

Struts

Although not an individual element of the suspension system, it’s still important to know what a strut is. A strut is the name given to the spring and shock absorber. For example, a shock absorber wrapped in a leaf spring is called a strut.

Anti-roll bar

Finally, the anti-roll bar is one last component of a suspension. It works to prevent the car’s body from rolling when driving on uneven roads or cornering. This bar is a metal rod that connects the left side and the right side of the car’s suspension system. When the suspension moves due to irregularities in the road, the anti-roll bar transfers the energy to the opposite wheel.

Thus, the anti-roll bar facilitates an even, smooth ride while simultaneously minimizing the odds of the car rolling while turning a corner. Anti-roll bars are now a standard component of the suspension system in almost every vehicle.

Signs that your car suspension is in bad shape

Now that you know about the different components that make up a car suspension, it’s time to dive into the subject of car suspension issues. The reality is that if you’re a driver, you may run into problems due to your car suspension. Knowing what to look for and spotting them early so that you can take your car to the mechanic is critical. Below, we outline a few telltale signs that something may be wrong with your car suspension:

A loose steering wheel

By a loose steering wheel, we don’t mean that the steering wheel is coming loose from the car. Rather, we mean that the steering system feels less tight when you steer. If your suspension is in bad shape, it can make your car less receptive to steering. For instance, it might be harder to drive in a straight line and the wheel might feel looser as you steer. Please note that a loose steering wheel can also be a symptom of poor steering alignment, so if you notice any steering issues, it’s best to have your car looked at by a professional.

Your car bounces when driving

As you now know, a car’s suspension is designed to absorb imperfections in the road, like rocks, potholes, cracks, or speed bumps, ensuring a smooth and comfortable ride. If your suspension isn’t functioning as it should be, you may start to feel these road imperfections. In other words, if you’ve noticed that your driving experience has started to involve more bounces, dives, or bumps, it’s possible that your car’s suspension is in poor condition.

If you can feel the bumps in the road more, not only does driving become less comfortable but it also becomes more dangerous. The more that your car feels the road, the more likely you are to lose control of the car.

To test if your car is bouncing or diving more than normal, press down on the front and back bumpers when the car is parked. The car should return to its normal height with no more than a single bounce, if that. If it bounces up and down multiple times, then the odds are high that there is an issue with your car suspension.

The reality is that you may have to replace or repair your vehicle if there is a major issue with the suspension. For more information on how long cars last in Canada or how long a car battery lasts, contact BrokerLink.

Your car leans when parked

A car should always sit flat when it’s parked. If you find that your car has started leaning toward one side or a specific wheel at one corner, it probably means that you have suspension issues.

Specifically, you are likely having issues with the suspension on a particular wheel or set of wheels. To confirm if your car is leaning when parked, look at the wheel well between the tire and the body of the car. It should be the same distance all the way around the vehicle. If it’s not, then your car is leaning and it could mean a problem with your suspension.

You notice strange noises

A third sign that your car suspension is in bad shape is if you start to notice weird noises coming from it. Listen closely to see if you can hear any clunking, squeaking, or knocking sounds coming from under the car. If you notice this, it could be due to a failed suspension.

As you notice strange noises coming from your car, it’s strongly recommended that you take it to a professional as soon as possible. Problems like this can get worse if left unattended.

Driving your car has become uncomfortable

One last warning sign of a bad suspension is if driving your car becomes uncomfortable. Comfort is crucial, especially given how much time we spend in our cars.

Thus, it probably won’t take long to notice harsh vibrations or bumps. If it feels like you can suddenly feel every tiny dip in the road, the odds are high that a bad suspension is to blame.

Your car dives when braking

A car that nose dives when braking likely means that there is a suspension issue. A diving feel when braking is the sudden compression of the front suspension, and this is not a good sign.

Tires are worn unevenly

Tire wear and tear is common, but if the tires on your car are wearing unevenly, it could mean trouble with the suspension. Specifically, it could indicate that the car suspension is putting uneven pressure on the tires, which means that it isn’t functioning as it should be. Examine the tire tread every so often to ensure that the tread depth is adequate and that the tread is wearing evenly all the way around each tire.

Car insurance for bad car suspension

If your car suspension is damaged in an accident, car insurance may cover you. There are many types of auto insurance out there, some of which can cover the cost of repairing your car suspension in a certain set of circumstances. That said, auto insurance doesn’t typically cover general wear and tear.

However, if your suspension was damaged in an accident with another car or it was damaged in the process of being stolen or due to a fire or windstorm, your insurance provider may pay for the repair costs. Contact BrokerLink to learn more about how car insurance works and how it can protect you against a bad car suspension.

Contact BrokerLink for more information on how car suspensions work

If you still have questions about how car suspensions work and whether car insurance will cover you to repair or replace a broken car suspension, contact BrokerLink today. We are auto insurance experts and have a team of fully licensed insurance advisors who are ready to help you find a great policy.

We specialize in customized insurance coverage that doesn’t break the bank. So if you’re looking for affordable auto insurance that will cover you against a wide range of risks, look no further than BrokerLink. When you give us a call, you will be matched with an insurance broker who will help you navigate the ins and outs of purchasing an auto insurance policy. They can explain what documents you need for car insurance and even provide you with preventative auto maintenance tips that can help you save money on insurance.

We also offer a variety of other auto services to customers. For example, we can provide you with car maintenance for road trips and winter car maintenance tips. We also offer free quotes to all customers. BrokerLink’s car insurance quotes are reliable, accurate, and 100% obligation-free. To request a free quote, give us a call, send us an email, or visit us at one of our 200+ insurance offices across Canada. You can also use our online quote tool to receive a free quote in minutes.

Get an auto insurance quote [phone]