Date: Fri, 7 Sep 2001 19:43:09 -0400
Reply-To: Dennis Haynes <dhaynes@OPTONLINE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Wheel Bearing realities.
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Syncro front wheel bearings are similar in design to many front wheel drive
vehicles. These types of bearings are pretty much a commodity now with
country of origin having little effect on Quality all though there are some
exceptions. The bearing missing a seal is not a quality problem as much as
application. In the industrial world bearings are available in any size with
0,1, or 2 seals. Since the Syncro uses seals pressed into the housing, the
bearing itself does not need any. I've done a number of Vanagons that did
not have any seals on the bearing from the factory. Most Chrysler and Asian
cars use open bearings relying on a set of housing seals. Non Syncro VW's
only have the bearing seal so it is important. Many cars also use a roller
bearing instead of the ball bearing the VW uses.
In my experience, most premature wheel bearing failures are due to improper
installation or another worn-damaged component. If you used a hammer. your
done. If you pressed on the inner race to seat the bearing in the housing,
the races will be damaged. If the hub is damaged or worn, that will also
cause the bearing to fail.
The Looseness you reported indicates to me that you have a worn/damaged hub,
CV joint face, or the CV axle nut was not properly torqued. The thrust
surface on the hub must be perfectly clean and free from burrs. Burrs are
often created when pulling off the inside middle race. When the hub it
pressed into the bearing, it must be a tight fit all the way through. The
inside (middle of van) end will often wear causing a loose fit. This will
soon wear the new bearing causing the hub to wobble again. The hub will need
to be replaced (dealer list $436). You also need to check the face of the CV
joint. The joint face and axle mounting nut/washer provide the clamp load to
hold the bearing together. Proper torque of this nut is extremely important.
For best results it should not be reused. Beating on the rotors to remove
them will also damage the bearing. Excessive heat from the brakes will ruin
the grease.
I hope some of this helps. While I agree that auto parts have manufactures
cut costs and often provide junk, I feel that all failures need to be
evaluated and there are benefits to having some work performed by
experienced and qualified mechanics. The experience is also important in
determining the fitness of a part before use and knowing when parts are not
fitting properly. If the bearing was bad, it should have been obvious during
installation or within 100 miles.
Dennis
~20 years changing' bearings after the chain shops mess them up.
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