[urq] RE: Driveshaft vibration

[Ado Sigal]

Mike, if you marked and reassembled the prop shaft 
correctly, balancing isn't needed. Its already done 
at the factory (plates on the shaft), but since the 
shaft is now in different position
after changing the centre bearing (with the frame I 
understand), it needs realigning. If you marked the 
position of the c/bearing frame and returned it 
there, you need to do only vertical alignment (with 
shim washers), if not, both ways. IME, vertical 
alignment for new c/b frame should be set couple of 
mil lower than resting position, since it would sag 
with time. VAG would have this tool, but if you 
don't have one handy (or VAG is to bloody 
expensive), you can make the tool yourself. Let me 
know if you want instructions.

HTH,

Ado


Brady Moffatt wrote:

> HI Mike/All,
> 
> I had the same symptoms on my 4kq after replacing the center bearing. It
> turned out to be the u-joint. It was in perfect shape, but due to the
> extreme angles it was subjected to during removal of the driveshaft
> (guessing here) compared to its normal tiny angles, it got "stuck."
> Cleaning it up well did the trick.
> 
> So, maybe in your case, there's a pinched needle bearing or something
> causing the u-joint to stick.
> 
> There was no need to rebalance the driveshaft, either, since it was marked
> upon disassembly.
> 
> Cheers,
> Brady
> Urq, 4kq, Z
> 
> -----Original Message-----
> From: quattro-bounces at audifans.com [mailto:quattro-bounces at audifans.com]On
> Behalf Of JagerBond at aol.com
> 
> Well the 83 center driveshaft U joint crapped out the other day. I pulled it
> out and replaced it (specs the same as older Mercedes) as well as the center
> bearing (same as BMW). I was careful to mark the yoke and shaft for
> reassembly.
> Now I have a vibration up to 5 mph and back again at 50 mph on up. I pulled
> it out again and dropped it off at a driveshaft balance place and they can't
> balance due to lack of tools. Any BTDT? Anyone know of a place in SoCal (San
> Diego/Los Angeles) to balance.
> 
> Thanks in advance
> Mike Bond
> 2002 A4 1.8T
> 1989 80Q for sale
> 1987 4KQ
> 1983 UrQ WX
> 1981 UrQ WR
> 
> 
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