Spohn Adjustable Rear Setting

[The Q]

I have the upper and lower Spohn rear control arms along with their adjustable Panhard bar. I got the thrust angle set with the Spohn Panhard bar. My question for those that are running the adjustable upper and lower control arms, what are your measurements for centering the rear in the wheel well? I 've checked the pinion angle, but realize it will need to be corrected when I center the rear end.

 

[charonblk07]

You will need to measure how much you need to move the rear tire back, it will be different on every vehicle depending on cab type and box size and how much drop. Best thing to do is lengthen the lower control arms until it's centred then adjust the pinion angle. It's best do have this done on an alignment machine though because you can get it centred to the box but your line of thrust can be out compared to the frame.


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[Dubstep Shep]

The problem with having all these adjustable arms is that changing one thing will almost always change another. You'll have to go back and forth to get it right.

Both your upper and lower arms are going to move the axle front to rear AND change the pinion angle. Assuming your thrust angle is small, you can always correct it later. The way I would start is by getting the pinion angle set or the wheels centered, whichever you prefer. Then set the other one as precisely as you can, and measure the first. If it's still good, then congratulations! Otherwise, you now have to go back and start making minor changes until it all checks out. Hopefully your thrust angle is correct, but if not get it down and double check all your other measurements.