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Propeller shaft / carrier bearing. Replacement



Seems to be a rash of this stuff

I just sent the following to Duane this morning and to another lister
several days ago and now I'm starting to feel like Steve Buchholz's
forwarding service. He did write a very good dissertation on replacing the
bearing. Good work Steve.

If you talk to Audi, they want you to replace the whole drive shaft. Not a
cost effective option.

I included a couple of previous posts from Steve Buchholz who
describes the process of replacing this bearing and has FAG part numbers.
These are fairly common bearings and many manufacturers make them. expect
to pay $15-$25 for the bearing from a bearing supply house. Check your
Yellow pages. 

The third option is what I am doing. Seems that the whole carrier assembly
is available that includes bearing and the mounting rubber. Catch, this is
a BMW part. My mechanic has the part now; and we are waiting for his new
hoist to do the work. Should have been done last week. I hesitated to post
the part number to the list until mine was installed and all doubt about
it working was erased. This was one of those "parts guy has customer who
has..." so, always a doubt until verified.  Cost of this part is around
$70 (haven't gotten the bill yet) and has the advantage of replacing all
the mounting rubber. Steve B says the rubber usually isn't bad. However
looking at the part, I could see how it might sag or could get brittle
with age so I decided to try the BMW part route. Besides, my mechanic was
proud of finding this and I want to keep him happy!

Hope this helps


Bruce
bbell@csn.net


Here they are one after the other!  Steve Buchholz is still on the
q-list. BTW 2nd message has part #s


Date: Mon, 9 Jan 95 09:42:51 PST
From: steveb@newkla.kla.com (Steven Buchholz)
To: quattro@swiss.ans.net
Subject: Replacing axial bearing (&/or u-joint) on quattro driveshafts
Sender: quattro-owner@swiss.ans.net
Reply-To: quattro@swiss.ans.net

I hear that this post didn't make it before ... and to think I stayed 
late on Friday to make sure it got out for the weekend!  Oh well, let's

try again!

This post is in response to a direct e-mail from Bruce Bell who 
was wondering about a noise for which the source could not be 
identified.  Since someone else was interested in this info I 
decided to post it to the group.  

A few years ago I had a noise that came from the driveshaft between 
the center to rear diffs.  I found that Audi considers this drive-
shaft a unit and so individual parts are not available for it.  I 
took the driveshaft off the car and found that it was not too dif-
ficult to disassemble and the bearing & u-joint were available from 
non-dealer sources.  This was done on an '83 ur-Q.  I am including 
information from pages 39.42-39.44 of the Audi 4000S, 4000CS and 
Coupe GT Official Factory Repair Manual 1984-87 Including Quattro 
and Quattro Turbo.  Here is a quick rundown of the procedure:

SPECIAL TOOLS: Other than metric socket & open-end wrenches all I 
  needed was one of the 12 point modified hex keys that is needed 
  to remove the socket cap bolts that hold the CV joints to the 
  drive flanges.  Bentley shows a home-made alignment tool (which I
  didn't make).

PARTS NEEDED: It is recommended that the CV joint seals be replaced, 
  these seals go between the CV joint and the drive flange and are 
  available from the dealer.  I don't have part numbers for the bearing
  or u-joint, but the bearing is a standard FAG part.  I was able to
  get a replacement for the u-joint by measuring the dimensions of the 
  cap & spider (This was necessary because I broke one of the needle 
  bearings when I was putting it back together!  BE CAREFUL)

BENTLEY's CAVEATS: Do not bend driveshaft, always store and transport 
  in parallel position.  Tie up shafts when removing and installing 
  driveshaft.

STEVE'S OPINION OF BENTLEY'S CAVEATS:  If you've got the car up on a 
rack it might be possible for the driveshaft to hang down far enough 
to cause a problem.  If you are working under a car on jack stands all 
that is probably needed is to protect the CV joints from contamination.

DRIVESHAFT, Removing: (From Bentley)
- Detach driveshaft from transmission flange.  Tie up shaft end.  
  [I recommend putting a heavy duty plastic bag (ZipLock) over the end 
  of the CV joint.]
- Detach driveshaft from rear final drive flange.  If necessary en-
  gage differential lock and block wheel.  Tie up [and bag] shaft end.
- Detach center bearing from body and take out driveshaft.

[Installation is the reverse of removal]
NOTE: Driveshaft must be adjusted [during] installation

Tightening torques:
driveshaft/trans. flange       55 Nm(40 ft-lb)
driveshaft/final drive flange  55 Nm(40 ft-lb)
center bearing/body            20 Nm(14 ft-lb)

The Bentley manual has several pictures and special tools for adjust-
ing the driveshaft during installation.  The whole idea of the proce-
dure is to ensure that the two halves of the driveshaft are as co-
linear as possible.  During installation the center bearing housing 
can be adjusted up & down with shims and left and right with slots 
in the mounting holes on the housing.  I marked the bolt locations 
on the housing and installed the same shims that were originally 
present.  
***
AFTERTHOUGHT INSERTED AT AN APPROPRIATE LOCATION:  You might want to 
test the axial bearing and u-joint at this point to verify that they 
need to be replaced!  The bearing might have a gritty feel as it is 
turned or make noise as the housing is spun as fast as possible.
***
Now that you've got the driveshaft out you will see that there is a 
nut that holds the fore end of the u-joint yoke to the the fore-shaft. 

It was not possible for me to fit an open-end wrench in there to 
loosen the nut until I had disassembled the u-joint & yoke (but I 
would recommend trying it because it would certainly be preferrable 
to keep the u-joint intact).  This was done by removing the spring 
clips for the cups in the fore-shaft yoke and then using a socket 
as a drift punch to remove the cups.  It should be possible to remove 
the spider from the foreshaft yoke after both cups have been removed, 
but it seems to me that I removed all 4 cups for some reason.  I re-
commend keeping track of which cup attaches to which leg of the spider,

but that probably doesn't matter since they are machined parts.  
While you're at this point it is possible to check for proper lubri-
cation of the bearings in the u-joint and scoring on the bearing 
surface of the spider.  
***
ANOTHER AFTERTHOUGHT: I used a mallet and sockets to disassemble the 
u-joint.  It is probably much more civilized to create a makeshift 
press using appropriately sized sockets and a bench vise.
***
With the u-joint disconnected from the fore yoke it should be possible 
to get a socket in there to loosen the nut.  I held the fore-shaft in a

vise to keep it from turning.  Once the nut is removed the yoke can be 
taken off (it is splined to the fore-shaft.  You may need to squirt a 
little penetrating lubricant in there to help.  

Once the yoke is removed the axial bearing and housing can be removed 
from the foreshaft.  The bearing was not pressed on, but it did take a 
little work to get it off.  

Looking at the bearing & housing it will be apparent which way the
bear-
ing comes out.  It is pressed in, but it isn't too tough to press the 
bearing out with a mallet and something large enough to keep the
housing 
stationary (I don't remember, but I probably adjusted the width of the 
vise jaws to be about the OD of the bearing and then used a socket as a

drift punch (love that Craftsman guarantee :)  It wouldn't be a big
deal 
to take the thing to a machine shop to do it right.  The part number
for 
the bearing can be read at this point and a suitable replacement
procured.
(I'll try to remember to look around this weekend to see if I have the
old
bearing laying around for the actual part #, but I think it is long
gone)

Reassembly is the reverse of disassembly, but be very careful when
reassem-
bling the u-joint.  It is tough to know if one of the needle bearings
has 
fallen into the bottom of the cup while you are driving the end caps
back 
onto the spider.  As I recall I had to insert the spider into the fore-
shaft yoke (after reassembling the fore-shaft, bearing & housing and
fore-
shaft yoke of course!) and then install the cups by hand.  It is
probably 
best to use a vise to get the cups inserted as far as possible into the

yoke (maybe even all the way with the help of a couple of sockets). 
Then 
replace the spring clips and you're ready to reinstall the driveshaft
in 
the car.  Go ahead and grease the u-joint before installation (service 
interval is 15K miles).  Also remember to clean off the sealing
surfaces 
on the CV joint and the mounting flanges and to replace the seals when 
everything goes back together.  

All in all the procedure is not too involved and I'd rather do this
than 
change a stupid water pump!  I replaced the bearing on the ur-Q shortly

after I got the car, and it's given me ~8 years of trouble free
service.  
I have tried to be thorough in my description, but feel free to contact

me if you need further clarification!

Glad to have a chance to help out on the net!
Steve Buchholz
s_buchho@kla.com

BTW - I didn't get a chance to look up the bearing # last weekend.  Let
me know if anyone would like me to head up a posse.

---------------------------------------------------
Date: Thu, 21 Sep 95 07:19:15 PDT
From: steveb@newkla.kla.com (Steven Buchholz)
To: dlawson@ball.com
Subject: QTC/other quattros?: Drive-shaft axial bearing number
Cc: quattro@coimbra.ans.net
Sender: quattro-owner@coimbra.ans.net

Well, I looked in my toolbox this morning and found that I kept the 
original axial bearing, so I am quite certain that I have the right 
number :)

The original bearing was made by INA with a part number of: 6006RSR

The replacement was made by FAG and had a few more numbers on it (at 
least the box had more numbers):

	6006.2RSR.T.C3

BTW - for those of you who do not know this already, even though
Audi considers the unit to be a single replaceable module and thus
will not sell repair parts, I have found it to be quite rebuildable,
with parts readily available.  I posted a rebuild procedure quite
some time ago but I haven't seen it in the archives as yet.  Send
me direct e-mail if you would like a copy.  Caveat ... this was
done on an '83 QTC, but from looking at the driveshaft on the '88
5000 it looks like it may still apply, but YMMV.

Hope this helps!

Steve Buchholz
s_buchho@kla.com
San Jose, CA (USA)