Wheel bearing again !!

[Fred Munro]

In addition to Mike's points, improper installation (i.e. pressing on the
inner race during installation) will significantly shorten bearing life.

Fred Munro
'94 S4


-----Original Message-----
From: quattro-bounces at audifans.com
[mailto:quattro-bounces at audifans.com]On Behalf Of Mike Arman
Sent: October 6, 2004 7:53 AM
To: quattro at audifans.com
Subject: Wheel bearing again !!



>From: "Greville Bowles" <zaphod at cansafe.com>
>Subject: Wheel bearing again !!
>
>After only 15 months on the car (18,000 km) my rear wheel bearing have gone
>again. This can't be normal wear, can it? Perhaps the bearing I used were
of
>poor quality. They were not expensive, as I recall.
>What other factors should I look at when I replace them this time?


Yes, something is very wrong here - these bearings almost never give
trouble.

Please describe the failure mode - Rust? Spalling? Excess heat (bearings
turned blue)? Noise? Looseness or play? Excessive tire wear?

All the seals in place and correct? Do they actually touch the surfaces
they are supposed to? If the seal is too large, water will get in and ruin
the bearings, if it is too small, it will burn.

Correct grease, correct amount, did you get it INSIDE the bearing, not just
on the surface? (a messy, tedious job, but necessary).

Correct pre-load on the bearings?

Any spacers missing or in the wrong place?

Bearings are not terribly expensive, so price isn't a good guide - unless
they came from Wal-mart or something - then the quality of the bearing
itself might be suspect.

Why did the first set of bearings go bad? Perhaps someone installed the
wrong bearings before you got the car, and you replaced them by looking at
the part number on the bearing and not double checking it in the book?
(This is a stretch, but possible - and 99.999999% of the time, the part
you'll find here is correct, but in this case, we want to check everything!)


Best Regards,
Mike Arman