Wheels/Tires Hard Metallic Knock from Front Wheel Bearing Are
Hard, metallic knock from area of wheel bearing on front axle when cornering slowly or while parking
Topic number L133.25P051401
Version 1
Design group 33.25 Axle housing, stub axle
Date 04092013
Validity Model 164 as of VIN 164 ###.#A 557 500
Model 251 as of VIN 251 ### #A104835
Reason for change
Complaint:
When negotiating a gentle corner at walking pace (58 km/h) or while parking / maneuvering, a single, loud metallic knock is
heard from the area of the wheel bearing on the front axle.
Cause:
Wheel bearing bore in steering knuckle may not have sufficient press fit, therefore insufficient overlap between wheel bearing
outer race and steering knuckle.
Micromovements result in the relevant noises.
Remedy:
Replace steering knuckle with wheel bearing.
In the case of followup repairs (steering knuckle already replaced), only replace the wheel bearing and secure it using "Loctite
648"
Note:
Use the Chassis Ear to facilitate diagnosis.
Experience has shown that in many cases the noise is caused only by the steering knuckle on the lefthand side in the direction
of travel.
For this reason repair the lefthand side first.
To date we are only aware of problems occurring on vehicles produced from October 2009 onwards.
