How-to-guide

Spotting defective shock absorbers

Accidents or serious installation errors can cause impact damage to shock absorbers. It is therefore advisable to look for damage to car axles and damper attachments and to carry out professional wheel alignment.

The ramifications of defective shock absorbers include various negative effects on vehicle handling and safety. That is why competent damage evaluation and repair by a mechanic are especially important.

Jammed damper

Possible causes:

  • Piston rod bent, e.g. due to an accident
  • Extreme trapped stresses, e.g. from incorrect installation

Consequence:

The piston rod jams in the guide and the damper jams.

Stem mount broken off

Possible causes:

  • Stresses caused during installation
  • Fastening nut tightened with excessive torque
  • Assembly using impact wrench

Consequence:

Material overstretched, stem mount breaks off.

Comment:

Never use impact wrenches for assembly!

Broken off rod eye

Possible causes:

Rod eyes crack or break off completely for the following reasons:

  • The end stop for the spring path is defective or missing (e.g. due to an accident). This means that the damper must perform the end stop's function, which causes excessive strain.
  • Incorrect adjustment of the air spring level
  • Excessive strain caused by extreme use on poor roads
  • Shocks installed with trapped stresses

Consequence:

The defective rod eye restricts or completely prevents the damper performance. The vehicle wanders and makes loud noise

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