The ZJ front shaft is about 2" longer than an XJ one. So you only cut about an inch off the rear output. Doing so gives you a lot of spline engagement but I'm thinking that is the issue.
That much engagement also allows for the weight of the rear shaft to lever against the yoke. My vibe is really like a very heavy resonance. Resonances are always due to looseness and/or cylindrical issues.
I'm going to cut the yoke so I only have like 1-1.25" of spline engagement.
My wife rarely even uses 4wd so strength isn't an issue in this case.
We'll see tomorrow afternoon if it helps...
