My wrangler is a 2001 TJ. My precious has developed a vibration or rubbing or grinding when the suspension compresses or rebounds. It doesn't take much, just moving off its regular ride level. It started out feeling like a tire rubbing but there was no tire rub. It has gotten worse over a couple of months. It doesn't have a lift but does have 31-10.50/15s. I've checked the rear diff, pinion bearing and u joints. Could it be in the front drive line? It feel pretty much like its right under my seat. Please help if you can. Thanks.