I have a 2008 JKU 4 DR. It had a 1 3/4" Daystar spacer lift prior. The Rubicon Express 3.5" standard short arm coil lift instructions suck.

1. I'm not oblonging the holes. So i doubled the cost of the lift and bought adjustable front and rear control arms. These control arms did not come with instructions.

2. What length do you set the front upper control arms too? If I leave the 1 3/4 spacer in the front too? What is the proper pinion angle for the front? All of the images I find show from axle to transmission, not axle to transfer case. Is the shaft suppose to come out of the axle straight so there is no angle at the axle end and only at the transfer case?

3. The front track bar. If you use the measurements that the instructions give you, it doesn't reach. If you make it reach it shifts the axle to the drivers side. Tips?

4. The rear upper control arm. What is the proper pinion angle for that axle to transfer case? Is there an angle at the axle or is that supposed to be straight and the only angle being at the transfer case.

5. Do I need to cut a notch in the transmission skid plate to clear the driveshaft now?

It should be noted that with the 3.5" lift coils, I gained 4.25" of height in the front and 5.25" in the rear. 6" in front with the daystar spacer left in. Rubicon Express states it is normal and they will settle (WTF?) and that maybe my old ones were that sagged out (62k miles). I have a heavy front bumper and winch, and a Wild Boar fiberglass hardtop. Pre-install it raked pretty heavy in front. Because of this, i had to buy longer brake lines too. I don't care what they say about the brake line relocate brackets...but i can't gain another 5.25" out of my stock lines. Pictures help if you got them.

 

I'm debating returning the control arms and going with the AEV relo brackets. Thoughts on this? Pros/cons. Why do they only make the brackets for the front? Brackets are $100, front and rear arms were $500

 

The front 3.5" coils gave 6"? Plus the 1.75" spacer that was removed for a total of almost 8 inches of lift? Wow...

For driveshaft angles, you can find a lot of good info on Tom Woods driveshaft website, in both the JK and the Tech Info areas. The diagrams show the pinions level with the tcase output for stock shafts, and pinions pointed up at the tcase output for aftermarket double cardans. Up front, you are going to have to make some decisions and compromises between caster angle and pinion/driveshaft angle. You might look into cutting/turning the housing, or a Spyntec kit, or ... --> dropping way down on the lift height.

Control arm lengths, no clue. Never seen a JK lifted that high, and besides, you need to do some experimenting with the angles rather than just using someone else's measurements.

If you plan on taking it offroad, yes, you should probably go ahead and notch the crossmember skid.

 

Sorry, 6" was total gain with the spacer. So 4.25 " gained in front and 5.25" in rear fom coils. 6" total in front. Edited original post

 

Square the length of the factory control arm length then add the actual height gained squared, once you get that sum take the square root of that and that should give you your length.

 

Got the front buttoned up. Looks like I have to drop the gas tank to get to the rear upper control arms. The death wobble is back. Hoping an alignment fixes it but I have a feeling it's the track bar. My last one I replaced the bolts with larger diameter ones and that fixed the problem. The bolts went in way to easy with this track bar.