Hey guys I have 1990 XJ 4wd and about 3 maybe 4 weeks ago I did a 3inch suspension lift consisting of Ford F-150 coils in the front and 3 inch blocks in rear and this morning I now have a high pitched humming noise in the rear and ideas?

 

Sounds like a pinion bearing, or wheel bearing, or any of the 10 bearings in the rear end that seem to hum in every xj.

 

I hear the same thing, just did my 5" lift with 31's. Is that humming bad, or just something to keep an eye on?

 

It was pretty bad I just popped open the pumpkin and there was no oil in it at all so i filled it up and it quieted it down about 60% but its still there.