E46 325xi - Driveline shudder in reverse - similar to locked diffs
This is my first post to the forum. I recently had a 2003 325xi fall into my lap - it was a deal too good to pass up; and I've been meaning to try out the other AWD systems from various manufacturers. Our last 7 cars have been Audi's - I consider myself an expert in owning and maintaining them. The only thing my vehicles go to the shop for is tires and alignment (20 years shop-free!)
I've searched the forums, and the web in general, but I am unable to find a solid answer to my question:
When I back this vehicle up with the steering turned at a modernate to full angle, the car shudders. This "shudder" is *exactly* the same as when the rear diff, or the center diff (in a non-torsen vehicle) is locked and the vehicle is turning. It feels as thought the tires aren't able to turn at the large difference in rate between them.
My understanding of the E46's AWD system is that all three (center, front, and rear) differentials are open (I know the center is a transfer case, rather than a real differential). But, something must be happening in the center diff to force the 68/32 torque split. I suspect this is the issue - if this is normal behavior.
Is this driveline shudder (one tire "scrubbing" since it can't turn at the rate it would like) normal? The car seems to drive fine, even at the limits - the only symptom is when reversing and turning.
Thanks for the help in advance.