JLUR Upper Control Arm Swap adjustments?

[dannko]

Received my Rock Krawler adjustable upper control arms for my 18 JLUR, has Mopar lift, but already replaced isolators with USA Alloys, replaced track bar with Rock Krawler adjustable, replaced damper with Falcon 2.2 adjustable, but would like to add about a degree of caster, so adding these arms.

Here is the question, without having to do a lot of trial and error, does anyone have an exact calculation of incremental inches changed to degrees? Example if I shorten it 1/4" what degrees of caster should that add?

Also, can I just switch the upper arms without loosening all the suspension bolts and then retorquing all? I have to say, that torque job is just too hard on an old man laying on the ground. I figure I can just swap one arm at a time, then torque the arms up after I have both installed.

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[Rock Krawler Suspension]

Do you have a current print out of the alignment that is on the Jeep now and a magnetic angle finder?

If you have a known caster spec currently, say hypothetically 4.2 degrees and you put a magnetic angle finder on a flat spot on the front axle which gives you a reading of hypothetically 85.8, you can adjust the arms to get that hypothetical 85.8 to 84.2 which would yield 5.6 degrees of caster.

To shoot from the hip, at your question more directly, without knowing what your current caster is set to, but being somewhat familiar with the Mopar caster numbers, I would start at 1/8"-3/16" shorter than the factory upper arms. Also, we would typically recommend using front lowers before front uppers for caster adjustment without sacrificing wheelbase.