need help diagnosing drivetrain problem on 90q20v

[Huw Powell]

> I put the car up on blocks, removed all 4 wheels, and was hoping to see
> 3 wheels spinning.  Instead, I see the fronts spinning and nothing
> happening in the rear, nothing in the prop shaft either.  WTF?  Bad rear
> diff?  Bad carrier bearing in the shaft?  With the car running and in
> gear, I can "help" the prop shaft and see both rear halfshafts turning,
> so I know the diff is not seized.

with such a tiny load on the system, and the diffs unlocked, it would
not be uncommon (IMHO) to see only *one* wheel spinning under those
conditions (all diffs unlocked).  slight differences in brake drag and
bearing/axle resistance to motion would be enough to make this happen
(most likely wheel to spin - LF)

I suppose "theory" would say that the torsen should "send" some spin tot
he rear by biasing itself, but would we really expect it to function
when there is virtually no "torque" to "sense"?

try immobilising those front wheels - the rears should end up up getting
the "spin" - and note how easy it is to stop them, too.  With gloves
on...

-- 
Huw Powell

http://www.humanspeakers.com/audi/

http://www.humanthoughts.org/