Warning! Malfunctions in the suspension and steering of the car can lead to a serious accident!
It is better to check the condition of the suspension by installing the car on a flyover, inspection ditch or lift, and if this is not possible, you can do this work on a free flat area, albeit with less convenience. In any case, you will need an assistant.
1. Carefully check the condition of the suspension parts. Pay attention to the condition of the rubber protective covers of the ball bearings of the front suspension. Ruptures of the covers and the presence of cracks on them are unacceptable, since in this case moisture and dirt enter the hinge, which lead to premature wear of the hinge. Be sure to replace damaged parts.
2. Check up a condition of rubber-metal hinges and rubber bushings of the lower levers, the stabilizer and extensions. The photo shows the right side of the car. On the left side, check the same places in the same way.
3. Open the hood, remove the plastic protective caps from the top supports of the telescopic struts and check the condition of the top support. There should be no cracks, tears, swelling, etc. on the rubber part of the support. After a preliminary inspection, you can proceed to a more detailed check.
4. Ask an assistant to grasp the upper part of the front wheel of a car standing on the road with both hands and shake it sharply in the transverse direction. In this case, you should observe the presence of gaps in the hinges of the front suspension. Pay special attention to the ball joint. Worn suspension joints must be replaced.
Helpful advice. The presence of a gap (backlash) in a ball joint, it is easier to determine if, when swinging the wheel, touch the ball joint with your hand.
5. If there is no play in the suspension joints, check the tightening of the nut securing the shock absorber rod to the upper strut support.
6. Jack up the car from the side to be checked until the wheel is off the road. Place a solid support under the threshold of the body (tripod) and lower the car a little to load the support. Rock the wheel in a vertical plane, holding the top with one hand and the bottom of the wheel with the other. Increased knocking from the side of the central part of the wheel indicates a large gap in the hub bearing.
Note. The knock in the hub bearing disappears if you repeat the test with the brake pedal depressed.
Warning! Do not attempt to tighten the hub nut more than the manufacturer's recommended torque to eliminate play. This can lead to the destruction of the bearing and the stripping of the threads of the nut and the shank of the wheel drive joint.
7. Inspect the telescopic suspension strut. Oil leaks indicate a malfunction of the shock absorber. In this case, it is required replace shock absorber or repair it. Check the integrity of the spring and compression buffer.
8. Check the brackets for attaching the stretch marks to the car body. The brackets must be securely bolted to the body and not damaged.
9. When checking the rear suspension, pay attention to the condition of the hub bearings, shock absorbers, springs, bumpers and fastening of the shock absorber rods to the body. You can tighten the shock absorber rod nuts from the luggage compartment by removing the seat belt reels and sidewall linings.
After replacing individual suspension parts, be sure to check and front wheel alignment. This operation must be carried out on a special stand in a car service, since improper wheel alignment leads to accelerated tire wear, increased fuel consumption, and deterioration in vehicle stability and controllability.
Pay attention to the exhaust system. Very often, due to the use of non-standard elements or a break in the suspension elements of the silencer, it can become a source of strong knocking, especially during regassing. To check, stop the engine, carefully inspect the exhaust system, check the reliability of the mounting and suspension of the muffler. Grasping the end of the exhaust pipe, shake the muffler up and down and from side to side - there should be no knocks.
Knocks in the suspension are often confused with the knocks of constant velocity joints (SHRUS) semi-axes of drive wheels. The sound - a sonorous metallic click - is especially evident when you sharply press the accelerator pedal with the front wheels turned at a large angle. As the CV joints wear out, the duration of the click increases. The only radical way to deal with such a knock is to replace the CV joints.