Definitely something going wrong though for an SKF part to only last a year.
Is the mounting surface in the upright still perfectly flat and clean? Dirt under the bearing or a warped upright would twist the bearing and damage it. I always file the surface lightly to check for high spots before refitting the bearing.
Is the hub itself still round and in good condition? Again, burrs or damage here could distort the inner bearing race. It would be prudent to replace the hub with a genuine new unit at this point - I certainly would if I was dealing with a car with this repetitive problem.
Are you torquing the four M12 bolts evenly and to spec? Ideally treat them like cylinder head bolts - tighten evenly and diagonally before torquing up, again so as not to distort the bearing housing.
Are you torquing the hub nut before you put the weight back on it? Spec for most big Audis is 200Nm plus 180 degrees with the final 90 degrees of that being done with the weight on the wheel. If you don't torque it at least the first stage before putting the weight on it, the bearing races can be damaged. That sort of torque is very difficult to achieve - for me its when my 1m breaker bar is bending about 15 degrees!
|