[wilkin250r]

I'll admit to my shortcomings.

Guilty. Yes, I have posted about this problem before, but that was somebody else's thread. I did not want to hijack it.

Guilty. I have done more work and research than I have previously indicated, but I'm still stumped. I didn't mean to come off as rude, I was intentionally "playing dumb" because I am fishing for new ideas. My next step is a reed tachometer, but most of them I have seen are in the realm of $400

My yokes are in phase, my tranny/driveshaft/pinion angles all seem to be within acceptable tolerance. In full disclosure, I don't have a really fancy angle finder, I'm just ballparking with a plum-bob and a protractor, but they seem to be really, really close. Most places I have seen say 3 degrees is an acceptable tolerance, and I can tell you that I am certainly within that range.

While I haven't disassembled the axle, the pinion bearing, axle bearings, ect ect, all feel smooth. Plus, I believe I have eliminated them as a possibility with my next step.

I have pulled the rear portion of the driveshaft, eliminating that half as a possibility, as well as the possibility of anything in the rear axle, and any kind of rolling resistance forces loading back into the driveline.

The vibration is still as strong as ever, but it occurs at a different rhythm when unloaded.