I did swap them around when I was running the hack n tap 242 case. After swapping in the 231 with AA SYE, none of the shafts I had here were allowing smooth operation. I definitely think that the Hack n tap style SYE was never going to be smooth.
I'm going to order a rear shaft from a premium shop Monday so I know 100000% it won't be an issue again.
As of today with an OEM ZJ front shaft installed in the rear and an Oliver's up front, there are no vibes up to 70 mph .
