Quote Originally Posted by tom4bren View Post
1. The joint requires scheduled maintenance
2. The 'drive' shaft and the 'driven' shaft must be parallel or a vibration will be introduced.
It is not that they have to be perfectly "parallel" to each other, it is just that the angle on the pinion at the transfer case has to be equal to the pinion angle at the differential at cruising/highway speed (in relation to the driveshaft). You normaly have to account for about 1-2 degrees of rotation of the differential (I think thy call it "loading") for both pinion angles to be equal at speed. This is why you need pinion angle adjustment after lifting or you will get drivetrain vibration. My next purchase will be adjustable lower links so that I can adjust the angle of the pinion at the diff to be equal to the pinion angle at the transfer case, because after lifting the angle at the transfer case has increased yet the pinion angle at the diff has in fact decreased (since lifting rotates the pinion at the transfer case to be less in line with the driveshaft, and rotates the pinion at the diff to be more in line with the driveshaft). Only other answer would be to have at least one joint on the rear driveshaft be a CV joint: