The suspension can be considered the part of a car that makes contact with the ground and keeps it in motion on the road. It can also be viewed as a system because of it’s makeup of various parts working together to achieve the goal of stability and maneuverability. Car suspension is in fact one of the most important system in a car because without it, there really isn’t any car. Since the suspension is the only part of the car that makes contact with the road, naturally there are bound to be wear. Common signs of such problems are noises from under the car.
Suspension system consists of the tyres, the steering, the shock-absorbers, the tie-rods amongst others ( You can also read this topic: Common Suspension Problems And Fixes) Any of these damaged parts could result in squeaking or creaking noise. We will take a look at the parts responsible for noises and possible fixes.
Most cars today use a steel coil spring. As the wheel moves down, the spring is compressed, and when the wheel moves up, the spring is stretched out. This movement absorbs the energy of any bumps on the road. So when these springs start to wear out, it likely could give out squeaking sounds. The best approach to fixing this problem is to replace the spring.
While the springs absorb kinetic energy when compressed, a shock absorber, more correctly known as a damper, is used to dissipate this energy by converting it into another form, most commonly heat. As the spring decompresses, that potential power is converted into kinetic energy. The shock absorber takes some of that energy and converts it into heat. Inside a shock absorber is a piston which moves as a tube filled with oil. The movement of the piston forces the oil through holes and valves to control the resistance of the movement, converting it into heat. If your shock absorbers are worn or damaged, you’ll experience far more bounce when you go over a bump because the springs don’t have anywhere else to release that kinetic energy. Still the best approach to fixing this problem is to replace the shock absorber.
When your car goes around a corner, the body will lean to the outside, leading to an uneven distribution of weight. Without a system in place to manage this, this could result in one side of the car coming off the ground or even rolling. Anti-roll bars are used to reduce body lean when cornering, and minimise the weight transfer to the outside tyres in the turn. An anti-roll bar is a torsion spring meaning that it resists twisting force. The anti-roll bar connects wheels on opposite side of the vehicles, so when one wheel is forced higher than the other during a turn, the bar resists the twist, keeping the car level. Worn out anti-roll bars gives out a creaking sound and must be replaced.
Lack Of Lubrication
Sometimes creaks in suspension and steering systems are down to a lack of lubrication between metal components such as tie rod ends and shock units. A properly lubricated system will also prevent significant build-up of dirt. However, even if grease seems to solve the problem, the squeak could be a sign of a greater issue and must be looked into.
Worn Ball Joints
Ball joints act as pivot points between the wheels and suspension and allow them to move freely. They are made up of a bearing stud and socket that fits inside a sealed lubricated casing. Depending on the configuration of the suspension, there can be upper and lower ball joints on each wheel, but no matter the structure, the ball joints will often bear much of the weight of the vehicle. While a ball joint will last for years, they can be damaged by general wear and tear or become less effective if the seals are damaged, which could allow dirt into the system or a loss of lubrication. This gives out creaking noise and must be replaced.
Damaged Suspension Bushes
Bushes or bushings are cushions made of rubber that are mounted on any of the joints in the suspension system. Bushes are fitted in order to reduce movement and minimise the noise and vibration. You’ll find bushes on the anti-roll bars, ball joints and shock absorbers – essentially anywhere where metal may be in contact with metal. As they are made of rubber and come under significant strain, suspension bushes will wear down over time. In fact, replacing suspension bushes is one of the most common advisories on an MOT. Worn bushes will cause a bad ride and this could be accompanied a rattling noise or clunk when going over bumps. You may also hear a squeaking if the bush has begun to perish. Damage to the bushes can be confirmed through a visual inspection.