Hi EJ - this is easy... since you've lifted it with blocks, what you'll need to do is go to your local 4-wheel drive store and pick up some "degree shims". Here's how you figure out what degree you need.
Since your driveshaft is a standard 2 U-joint system, you'll want the pinion gear on your rear axle pointed 2 degrees down from pointing directly at the output shaft / tail shaft of the transfer case. To say it another way... rotate / point the rear axle's pinion shaft directly at the tail shaft of the t-case, then rotate it down 2 degrees.
With a 3 u-joint system, you should have it pointing down 2 degrees, because that's *approx* how much axle wrap you'll get under heavy load. This way the driveline is in perfect alignment when there is the most load on the system.
So... here's how to measure for this...
- Get a long, straight pipe or piece of PVC and cut it about 1/8" to 1/4" longer than the length of the driveshaft (plus it's u-joints).
- Tape one end of the tubing next to the driveshaft (perpendicular) on the pinion side
- Rotate the tubing upward until it's perfectly in alignment with the tailshaft of the t-case, then tape it into place
- Place a rotating angle-finder on that tubing and take an angle measurement (e.g. 12 degrees).
- Subtract two degrees from that measurement (for the axle-wrap that I talked about) and write that number down. That's the angle of the degree shim that you'll need
In most cases, you won't need more than a few degrees of an angle shim. However, if you do need a lot (like 10 degrees), then you'll need to cut your spring perches off of your axle and weld new ones in place. If you think you need to do this, here's a tech article that we wrote on that: http://www.4x4review.com/Features/Tech/BeAGeniusClockRearAxle/tabid/293/Default.aspx
Once you have your degree shims, all you need to do is secure your vehicle and axle with jackstands, loosen the u-bolts that hold your axle to your leaf springs, and then put the shims between the lift blocks and your axle perch, then tighten everything up.
It may sound complicated, but it's very easy to do. Just be sure to tighten your u-bolts to the correct specification, and then check them again a week or so later to make sure they haven't loosened.
Hope that helps,
Rick |