suspension noob needing some help. Installed a lift that netted about 3.25-3.5 inches of lift overall on my 2dr Jk. I'm needing to adjust the pinion angle on my rear shaft to adjust for the lift ive installed but im confused on whether upper or lower arms will help me adjust pinion easier. Do i need both sets or can i just get away with adjustable uppers? i need to move my angle about 2 degrees.

Ive already installed front lowers but I was waiting on the rears until i got the lift on.

 

Upper for the rear to set pinion angle. Lowers to set axle centering inside wheel well

 

Thanks! I do have access to a set of fixed upper control arms but they are only 17 1/4 center to center and I have a feeling I will need something longer as those are shorter than factory ones. I’m not sure why they’d make them shorter than factory as I feel like that would push the pinion In the opposite direction

 

Yeah, front lower and rear upper are the general recommendation if only doing one set at either end.

But, either will do the job. Adj rear uppers are set a bit longer than stock, lowers would be a bit shorter than stock. The result is the same, the housing rotates and the pinion angles further up. Using shorter rear uppers, you are correct, the pinion would rotate down.

 

Have fun with the stupid nut/flange combo that holds the rear upper arm on the frame side It helps to have someone hold the arm in place as you hold the flange with the nut up in the frame rail and guide the bolt through.....unless you're an octopus with multiple arms.