LOOSE DIFF CUPS AND BUSHINGS (FIX)
10/05/2012 = I found part of my wheel hop issue...
The drive cups (gear differential shafts) on the diff are all loosey goosey and flopping/wobbling around = Causing the dog bone to flop/wobble = Causing the wheel to hop.
And the bushings were loose in the diff housing.
I have a spare back up diff that's never been used and I checked it = same problem, but not as pronounced due to being unused.
Now that I think about it, my RS4 Nitro had the same problem back in 2000.
Go figure.
I took that one apart; I upgraded the B070 bushings to 5x8x2 bearings (5x2x2.5 should work as well) & I shimmed the drive cups.
I used a variation of bobbyb323's fix to tighten up the bearing to diff fit = I used a 5/16" punched out circle of a zip lock bag (the same size I use for my center link ball cups) to shim each bearing.
I just placed it over the end of the diff hole, pushed the bearing in and trimmed the excess inside and out for each side.
Now the bearings are snug in the diff and the ball cups have a much better fit.
The rear diff has the same issue, but it's less noticeable because there is no steering action/stress going on.
PARTS USED
HPIZ694 Washer M5x10x0.5
HPIZ852 Washer 5x7x0.2mm
Zip Lock bag
Last edited by Marv; 11-10-2012 at 05:18 PM.