To anyone else with a low pinion D30 running a RE 3.5" lift (so actually, a 4.5" lift):

Is your front pinion less than perfect? Does your front DS vibe over 50mph? Mine does, it doesn't shake the whole car, it's more a noise than anything else, but it's semi-annoying.

Were you able to solve the problem? How? Rob from caster to pay the pinion? (I have adjustable UCAs, but they're already at the right length per that control arm vs lift height chart floating around the interwebs)

I put a 3/4" TC drop and it maybe helped slightly, maybe not, hard to tell, could be placebo. I don't want to keep the TC drop if I don't have to. And after thinking about it, could a TC drop make the front driveline angle even worse since it tips the TC up towards the front?

FYI- The rear is fine, I have a SYE and shims. I completely rebuilt the front DS and while it looks pretty, it changed nothing in terms of vibration/noise.

Is there a standard for judging what amount of vibration is actually doing damage? I may just be hearing noises and feeling things that stock control arm bushings muted. Looking for others' experiences with similar issue and what they did or did not do...

TIA

 

Totally skipped over the part where you said you already had adjustable UCAs. My bad. Like Fred said, having a t case drop and a SYE both isn't necessary.

 

 

I have no experience with the LPD30's but you should not have to use a TC drop kit with an SYE installed and lose even more clearance. I see you have Adj. UCA's I might suggest you try and set the pinion angle with it and measure for the alignment afterwards. You may want a set of Adj. LCA's also to center the tire in the wheel well this is what I did on mine.


My XJ has never been to an alignment shop only used the measurements I found on this site to set it up and have no issues after 3 1/2 yrs. now.


With the LPD30 anytime you lift the pinion angle is affected more than with a HP. I know others have dealt with this problem so I hope they give you more ideas than mine.