There was a thud in the front suspension on the bumps - what

Driving into areas with a rough road, drivers can hear a slight knock on the front suspension on small bumps. Such a symptom can make a large number of young car owners nervous.

The point here is not only in fear that some part may fall away while driving, but rather car owners are concerned about possible future repairs. The cost of the restoration of the suspension can cost about 500-1000 dollars. Therefore, it is possible to carry out diagnostic work independently, and later, having discovered a problem, you can also fix it yourself.


  • 1 Problem suspension
  • 2 Malfunctions with steering
  • 3 Stand support
  • 4 Problem in thrust bearing
  • 5 Ball bearings
  • 6 Problem stand
  • 7 Possible rare causes of knocking

Problem suspension

Possible causes of knocking in the front suspension lie in its levers. Complete with poor handling, possible culprits are often silent blocks. To diagnose them fit mount. It is used as an elongated shoulder. Deflecting the levers in different directions, there can be a significant backlash.

where there is a knock in the front suspension on small bumps

If the design is collapsible, then replacement of silent blocks will be required. This is done after dismantling the lever and pressing the Hob out of the hole. The operation will require special amendment. Before installing new silent blocks, they must be lubricated to reduce friction. Also required to clean the landing surface from dirt.

Steering malfunctions

Experienced drivers can suggest that knocking on the bumps in the front suspension occurs not only in the obvious problem nodes. Often, shock absorber racks are blamed for it, and the problem is not in them and not even in the support bearing on which young car owners sin.

The reason may disappear in the steering. Checking this node, which often produces a sound similar to the sound of shock absorbers, you can detect problems with the rail. Noises from it are usually heard from one side. An additional sign pointing to this element is a slight steering vibration. It can be felt while driving on a gravel road.

The sound comes from the interaction of the rack and gear moving along it. The gap can gradually increase, and the intensity of this increases. This is the result of significant development on the mating surfaces of the pair. You can jack up one of the front sides of the car and sway the steering rods in different directions.

when there is a knock on the front suspension on small bumps

At this time, we must observe their behavior. If there is a backlash, then an alleged thud in the front suspension, perceived by the driver, may arise from worn bushings.

With a possible rotation of the rail can argue about the gap in the pair. However, it is quite simply eliminated by tightening the rack to the gear. The bushings in which the workings were formed are also referred to as repairable products. Their repair kit is easy to purchase at the car shop.

See also: What kind of grease for wheel bearings is better

The steering joint can become the culprit of incomprehensible noise. When diagnosing it, you need to ask for help from a partner who, in the process of checking, will sharply rotate the steering wheel at small angles. At this time, the car owner must fix the housing, joint and finger. Unnecessary play will be heard immediately. Replacing this unit will cost much less than complete suspension repairs.

Stand support

The upper part of the support is the reason that there was a thud on the bumps in the front suspension. The rubber base serves as a damper damper for possible excess noise. But flexibility can be lost, and once, a base capable of returnable deformations, “stiffens” and begins to wear out.

what are the main reasons for knocking in the front suspension

Because of the sounds that have appeared, drivers can completely sort out the suspension, to spend a lot of money, time, but never get rid of the cause of noise. This problem can be identified by measuring the gaps between the support itself and the plastic limiter. Depending on the design, cars may be closed for this site. In the rest, the approximate average parameter should be about 10 mm.

Assign this node to the culprit only if there is a clear noise on one side. It is unlikely that uniform development will be on both sides at the same time.

Problem in thrust bearing

This sound is similar to the generation of a damper, but is more resonant. To detect a breakdown, it is advisable to remove the rack. There is a specificity in the failure of this bearing. The development of it always turns out unequal around the perimeter. Its greater degree will be at that moment when the movement of the car will be smooth, without turns.

when there is a knock on the front suspension on the bumps

Such a knock can disappear when moving to the right or left. If this happens according to this algorithm, then the "culprit" is found. Additionally, the test can be carried out with the help of a partner. He will have to swing the car vertically. The owner of the car under his vehicle will hold the suspension strut. You can feel the vibration by hand.

Ball bearings

Experienced drivers often call this element of the suspension a source of “classic” knock at the front of the car. However, this "disease" has its own specifics and affects more rear wheel drive cars. Therefore, motorists who do not change the VAZ rush to “change the ball”.

Working out on a hinge gives a beating when driving on a rough road.

The check begins with a wheel hanging on the problem side. Then, without rotating the disk, we try to turn it sharply several times to the right / left. To eliminate the influence of the bearing from the hub, the partner can squeeze the brake pedal during the test.

See also: How to replace the front axle support bearing

when does a thud start in the front suspension

In any case, you can check the anthers on the ball. Significant damage to this protection reduces the life of the entire hinge.

Problem rack

Practice shows that the rack can also produce sounds while riding on gravel. Although this is rarely the case, it is also possible to check this node. A heavily worn but still full stance is capable of transmitting shocks.

This is noticeable when getting into the pits when moving., while on the rebound, it does not work, and the spring sharply straightens. It turns out the wheel goes down sharply. Having stretched to the maximum length, and then, having adjoined to the opposite part of the pit, two blows will be formed.

It is possible to check the working capacity of the rack in the standard way, by swinging the car vertically, with an effort pressing sharply on the hood. The body of the car is obliged to return to its original position unshakably once. Such actions speak about the health of the site.

why is there a thud in the front suspension

In very rare cases, an unscrewed locking nut is capable of making noise inside the rack.

But then the car will sway during movement and lose controllability. Noises will not be like regular knocks, but will arise spontaneously. Required repair.

Failure of shock absorbers usually happens due to neglect of them. An oil of a certain viscosity is poured inside them. This indicator is also influenced by the ambient temperature. Too low does not increase the fluidity of this fluid.

An inexperienced driver who has slightly warmed up the engine oil may, without sparing the suspension, start abruptly by car. Due to such an effort on the most viscous little can be damaged small and fragile structural elements of the rack. It is also possible the presence of oil with high viscosity in sports cars. This stiffens the suspension.

Possible rare causes of knocking

For integrity or published noise check the stabilizer bracket. In its design are bushings with rubber elements. They are connected by a rather fragile beam. Sometimes it bursts and knocks when rocking a car. You can shake her hand on the wheels turned in the side.

when a knock is heard in the front suspension on small bumps

It happens that the supports, on which the engine is fixed, burst. While driving, the unmounted engine moves under the hood. With its prominent parts, it can knock on the body of the car. Such a knock is often confused with the sounds of a problem suspension.

Under the hood of a used car, various noises can occur. The reason is even elementary elements that are not tightened to the desired level. It is not always necessary to rush to the station to identify problems. Most of these causes can be identified and resolved by yourself.