Join Date: Dec 2001
Location: Belleville, Illinois
Thanked 22 Times in 17 Posts
Re: Setting caster
If you're going to use a cardan-joint driveshaft, the pinion should be at the same angle as the transfer case output shaft. You can measure that now, assuming you're not going to raise one end more than the other. Then the angle to be built into the yokes is the difference between the output shaft angle and the working caster you want when it's finished.
Typically the front output shaft points up slightly, so theoretically the pinion shaft should point down at the same angle. A lot of guys don't want to do that for clearaqnce reasons. You can tolerate some difference in the angles before the resulting cyclic vibrations get objectionable. Unfortunately I can't give you a an angle at which that happens. If you only lock hubs in on the trail, it's not too significant anyway, but you don't want a real big difference in angles.
If you're going to use a CV joint on the case, you want the pinion pointing at the CV joint. That will be a little more difficult to figure. You'll be raising it about 4". You'll just have to measure and estimate what the pinion angle will need to be.
You can then have the axel built, but leave the spring pads unwelded until you can set it on the springs under the Jeep. Rotate the axel until you have the pinion angle you want, and weld the pads in place.