|
Has the problem always been there. Are the rear control arm bushes nylon or rubber. Nylon will transmit more vibration to the chassis. When you did the tummy tuck did it raise the T-case as this will increase the angle on the rear double cardin. Have you measured the angle on the rear double cardin. I have 5 and 6 degrees for a total of 11 degrees on my double cardin and I have an XJ. The maximum recommended speed for a u-joint running at 5 degrees is 3000 rpm or 100kph for me. You appear to have more than 11 degrees. You could try lowering and raising the T-case a bit to see if that helps. Have you checked to make sure that the yoke on the diff is not flogged out allowing movement from side to side of the u-joint. If you have ever broken a u-joint on the rear diff it may have damaged the yoke at the same time. I had a DS built locally once and it was never any good and I ended up getting a front DS retubed to the correct length which is what I have now. Lighter is better. Also check to make sure the DS is not twisted , although you said that it does it with both rear DSs. I have found that genuine Dana Spicer vibrates less for some reason. Now that the vibration has been there for a while it may have loosed up everything. I had that cyclic thing that you are describing once, and it turned out to be a flogged out rear yoke on the diff that I believe was caused by the DS I had built locally.
|
