Rear suspension: the ultimate guide from SKF

What are the main functions of a rear suspension?

The main function of rear suspension (and the front one) is to keep the cars main body from touching the ground and maintaining the wheels on the road. Another function is to enhance the stability on turns and to make the ride more comfortable.

How does a rear suspension work?

A suspension system works with forces going up and down. The weight of the car pulls the car towards the ground, so there is a coil that pushes the car upwards to prevent this from happening. However, there must be another system to prevent the coil push from being excessive, which is why there is a damper. The damper’s main function is to absorb and reduce the compression and rebound that the coil has.

How does independent rear suspension work?

An independent suspension is one of the most common suspension systems along with the the solid rear axle. In order to understand one system, it is important to get the knowledge of the other. For this reason, we will first talk about solid rear axles. When one wheel is pushed up on a solid rear axle, the other wheel does the opposite..A rear independent suspension system allows each wheel to be raised and lowered without affecting the other wheel, providing a better level of tracking for a car fitted with this type of system.

Car suspension parts

• Coil springs. If you hit a bump in the road, the coil springs are the shock absorbing part.
• Shock absorbers. The damper or shock absorber is the part that absorbs and dampens the compression and rebound of the coil.
• Joints/bearings/bushings. These parts allow other movements beyond the “up and down” the coils and shocks can do. With them, the system can also tolerate sliding sideways.
• Rods/linkages. These parts are the ones that hold the suspension system together.

3 main types of suspension

• Leaf spring. It is used for heavy vehicles that will have to carry heavy weights.
• Torsion bar suspension. This kind of suspension provides more space and commodity (but it is less firm) than other suspension systems.
• Coil spring. The most common system, coil springs, can be found in independent front or rear suspension systems and in solid axle systems.

FAQs

In an independent rear suspension system, each wheel can be raised and lowered without affecting the other, providing a better level of traction for a car fitted with such a system. Better traction is one of the main benefits. Therefore, the advantages of this type of system appear when driving on uneven roads. In addition, as the wheels raise and lower themselves, the contact surface with the road is always the same, which prolongs the tyre's life and performance.

What are the signs of suspension problems?

• Your vehicle plummets when you step on the brakes. This is a clear sign of a worn suspension (old or high mileage).
• Your vehicle pulls to the side when you drive it. If you experience this, you may need to get your car checked by a specialist as it could be happening due to a broken suspension, or inaccurate wheel alignment, steering problems or tyres may be worn.
• Your vehicle has the sensation of drifting when you turn a corner. Here is a sign of a worn-down rear suspension system, where the system is not capable of maintaining the car stability on the road on the turn. In this case, the shock absorbers should apply to the road and the rear end feels slack.
• Your vehicle keeps bouncing after you hit a pothole or a bump on the road. The shock absorber, which is the part that absorbs and dampens the compression and rebound that the coil has, is broken. This can cause the car to bounce when it should not.
• Your vehicle no longer offers a smooth ride. The problem here can be related to several mechanical parts, it is recommended to get the car checked by a professional.

In any case, if you think your car is malfunctioning, a good practice is to take your vehicle to a professional mechanic. It could be dangerous and risky not to do so. Many of the signs we have discussed could also be caused by other mechanical problems that do not necessarily stem from the suspension system. Therefore, a thorough check to discover the causes may be the best thing to do.

You can check the following link to see all the suspension products SKF is carefully manufacturing for you, it is our priority to continue to create high quality products to ensure the safety of our customers.
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