Re: 200T Front End Noise

[Don Hoefer <hoefer@cary.eng.pko.dec.com>]

Peter,

My wheel bearing tutorial follows.  Your car should be similar.  Verify
with a service manual.  The CV joints are easier.  No expensive special
tools required.  Your hub nut probably requires a 32mm socket.  The inner
CV joint is probably held on with 8mm internal spline bolts (to remove the
drive shaft).

Since the noise only happens when you turn right and not left I would not
suspect the CV joint.  It could be a bearing or something rubbing.  The
bearings in the CV joint use the same part of their race no matter which
way you turn although one will be driven for one turn and not the other.
Jack up the left corner of the car and turn/wobble the tire by hand to see
if you can hear or feel anything or see if it is loose.

Don Hoefer
'82 Coupe
>>>>>>>>

I hope that this is not too long.  I have tried to cover the special details 
that make the job easier (or possible).  Most of this also applies to VWs, 
5000s, and quattro rear wheel bearings, with some differences of course.

Usually the first signs of front bearings going bad are a slight clicking 
sound when going straight or turning slightly, or funny, not quite right 
handling and tire wear (because the bearings are a little loose).  When they 
get really bad they will rumble, groan, and even squeak depending on speed, 
braking and turning.  The car will have very bad directional stability.  It 
will wear your brake pads a little more also.

I use the special tool by Scheley (I lost their catalog) available from 
Snap-On or Techtonics, about $185.  It consists of a long threaded shaft with 
a selection of disks to fit the various sizes of bearings used on VWs and 
Audis.  There is an extra adaptor required for later model 5000s.  I do not 
know about the new Audis.  They are probably similar.  This tool makes the job 
a snap.  If you can get this tool all you need to do is remove the driveshaft 
from the wheel hub and press out the bearing with the strut in place.  The tool 
comes with an instruction sheet.

First loosen the hub nut with a 30mm socket, then jack up the car and remove the 
wheel/tire.  To remove the driveshaft unbolt and remove the anti-roll bar, 
unbolt the ball joint from the bottom of the strut and swing or tap the control 
arm down.  Do not remove the ball joint from the control arm.  Remove the brake 
calipers and disk.  Hang the calipers from a bent coat hanger.  Swing the strut 
out and pull the outer cv joint and drive shaft out of the hub.  Slide the ball 
joint back into the strut for stability.  The tool comes with long bolts to 
press the hub out against the strut.  I found a cheap puller at the hardware 
store to remove the inner race from the hub.  Put the hub back on to the outer 
cv joint upside down with the old nut holding it on upside down also.  This 
gives the puller the dimpled end of the cv joint to push against.  If you are 
lucky, the inner bearing race will stay in the bearing assembly and will not be 
stuck on the hub.  Press out the bearing with the special tool.  I turn it with 
a 36mm socket and a 3/4" breaker bar.  The nut on the tool is held with a large 
adjustable wrench against the control arm.  I work up a sweat.  Don't forget 
about the snap rings,  remove them to press out the bearing, install the outer 
snap ring before pressing in the bearing.  Install the inner snap ring after 
pressing in the hub.  Reassemble everything in reverse order.  You may put 
the hub nut on but do not tighten it against the bearing (don't forget the 
big washer).  Install the wheel and tire with bolts snugged on and lower the 
car.  Torque the hub nut to the manual specification, then torque the wheel 
bolts.

Lubricate the tool well with anti-seize.  Put a small amount of anti-seize on 
the bearing and hub to make it a little easier next time.

In some cases the driveshaft can be juggled out by leaving the strut in place 
and removing the inner cv joint from the differential (twelve point 8mm bit 
required).  This works on the driver's side of my car.

If you do not have the special tool or access to a press you can try removing 
the strut and pushing them out with a hammer.  Support the strut well to prevent 
damage.  Use some object that fits against the bearing outer race and strike it 
with the hammer.  An old bearing works well (see below).  I do not think that 
a clamp or a vise would be strong enough to press it out.  Take one of the 
removed bearings and sand it slightly smaller and use it to press in the new 
bearing.  I tried this and one bearing worked fine for four years, the other 
bearing lasted for two weeks.  Two bearings, a new hub, (hub = $184 for 82 
Coupe!) and the special bearing puller later and I was set.  It is difficult to 
get the hub in all the way and straight without damaging the new bearing.  The 
inner race needs to be supported for this part of the operation.  The easy way, 
take the strut to a shop.

To remove the strut, follow the instructions above and use a puller to remove 
the tie rod end.  You may be able to tap it out with a hammer (leave the nut 
on the top of the threaded shaft so that you hit it with the hammer also and 
protect the threads.  If you don't have the funky socket for the top of the 
strut, use a pipe wrench around a cheap 22mm socket so that you can get the 
allen wrench into the shock shaft through the socket drive square hole.  Hold 
the allen wrench with an adjustable wrench.  Replace the tie rod nut when you 
reassemble, especially if you hit it with a hammer.  If the ball turns when you 
try to tighten the tie rod nut, use a pipe wrench to press the bottom of the 
tie rod end up, leveraging the opposite jaws of the wrench over the strut 
steering arm.

Speaking of damaging the bearing, pay attention to the procedure in the manual.  
It will probably say to loosen and tighten the hub nut when the wheels are on 
the ground.  Do not do it any other way.  Do not torque the hub nut with the 
car jacked up.  Do not roll the car with the hub nut loose.  You will need a 
new bearing in no time.  Torque to about 163 ft-lb, or what the manual says.  
You will know when it is tight enough, you can't turn the wrench anymore.  
Always replace the hub nut.  You can replace the bearing, hub nut, and ball 
joint nut only.  A "bearing kit" includes the hub nut, snap rings, and the nut 
and bolt for the ball joint.

For new bearings, FAG and Timken were OEM.

If a shop does this job and they do not have the special tool, they have to 
remove the strut so that they can take it to their press.  When the struts are 
removed and reinstalled an alignment is necessary.