939007876 - S017 FRONT SUSPENSION NOISE (WHISTLING/HUMMING)

Whilst driving, especially on unmade roads, there is a whistling noise coming from the front suspension. This diagnosis can only be made afterSee table Carry out the latter first.
If the problem is only on one side, carry out the checks and any operations on the appropriate side only.
0PRELIMINARY CHECKSAll OKProblems encounteredOperation
Having carried out the road test, during theSee table , there was a whistling noise from the front.Continue depending on the circumstances in which the noise occurs.End of diagnosisThe noise increases when cornering.

  • The noise increases when cornering
  • The noise increases in vertical oscillation conditions
Replace the wheel bearing complete with hub on the side where the noise is loudestOp. 4450C32 ONE FRONT WHEEL HUB BEARING, LH OR RH - REPLACE
This bearing is used by the ABS active sensors to calculate the wheel speed. It should NEVER come into contact with metal shavings because they could alter the gap and prevent a correct reading from the sensor.

  • Replace the wheel bearing on the side where the noise is loudest.
  • Move on to Step 1
The noise increases in vertical oscillation conditions.Move on to Step 1.
1BRAKE DISC CHECKAll OKProblems encounteredOperation
Check that the gap between the brake disc and the steel shield is sufficient.Move on to Step 2Gap too smallRestore the correct gap
2SHOCK ABSORBER STEM CHECKAll OKProblems encounteredOperation
Remove the wheel    Op. 4450B12 FRONT WHEELS (TWO) - R+R Check that the noise is not due to irregular friction between the shock absorber stem and the gasket, checking the condition of the stem chrome surface.End of diagnosisThere is irregular frictionLubricate the stem raising the dust cover with a layer of silicon grease.If the noise persists, replace the shock absorber    Op. 4410A12 FRONT SUSPENSION DAMPER (ONE), LH OR RH - FOR MCPHERSON STRUT SYSTEM - INCLUDES DISMANTLING/REASSEMBLY OF ASSEMBLY AT BENCH - R.R