Im running out of ideas.

I installed a 3" lift on my 01 xj. Now, when I accelerate I feel a short vibration on the drivers side near my left foot. It doesn't happen when I slowly accelerate but will happen if I get up past 2000 rpms. Doesn't matter if I'm turning or driving straight.

So far I've
lowered my tcase
Replaced swaybar bushings and end links
Steering stabalizer
Drilled and tapped new spring retainer clip
Checked rear drive shaft u joints (good)
Removed front drive shaft( still happening)
Replaced front axle u joint(I was sure this was the culprit)
Checked hub and bearings

Im wondering if my trac bar needs relocation, new control arms (all have new bushings) or tcase mount(looks good)

Help!

 

What is a "vibration specialist"?

Just a thought- but could it be your exhaust, since it's RPM-related? Motor mount? Does it happen when you rev in park or neutral?

 

Ahhhh man... I was even going to say " not in that way"

So it's not the motor mounts... Also doesn't happen in park or neutral.

I've pinpointed it under my left foot. Could it be because my trac bar needs to be relocated?

 

Well, I haven't done any lifting and am not familiar with what needs to be done to make it work right- but it would make sense, if the vibration wasn't there before the lift and the U-joints aren't operating at oddball angles. Under your foot is about where the lower control arm is located, no? Is that loose? Bad bushings?

 

The control arms are tight and the bushings were replaced about 7k miles ago.

I did have a heck of a time getting the control arms back on but they fit.

Also. I've had an alignment done too

 

Anyone?

 

T case tight? Tranny tight? Engine? My t case got loose and I have bad vibes past 15 mph.

 

In park/neutral there's no load on the engine. Exhaust is a possibility, but I'd imagine there would be some audible banging noise if it was hitting the transmission cross member.

When did you install the transfer case drop? Those things wear out transmission (and motor) mounts fast.

Also does this happen in ANY gear? How does your transmission fluid look? Red and not burnt smelling?

 

When you ask if the tcase is tight I assume you mean the mount? I can slightly move the tcase up but doesn't seem to be alarming... Also would that cause the front vibes when the front axle is off?

I installed the tcase drop about 2 weeks ago. The fluid was recently flushed and looked just fine.

 

Well the only thing under your left foot is the LCA, but you said you replaced that recently. Otherwise the only thing RPM related is going to be directly connected to the drive train. Being a massive steel box, feeling a vibe in one spot doesn't necessarily mean it comes from there, it could be resonating from elsewhere. I take it it was vibrating before the transfer case drop? (TCase drop done after lift?)

Also you haven't mention if this happens in all gears

 

maybe front or rear driveshaft angle ?

 

Ill have to check in different gears

I check my upper and lower control arms. My upper arm (connected to axle) has been sort of "smashed" or pushing into the bushing, leaving some of the bushing pushed out but still solid.. Wonder if that could be it?

 

This still occurs in various gears. Felt it up till about 40 mph

 

remove the rear driveshaft & drive it in 4 hi part time, see if it goes away.

 

never mind read back through and you got it aligned.