Hi All: I'm new to the forum, as I just adopted the '02 Sport from my daughter. She got my '14 Cherokee for Graduation! Thanks for all the advice! This was a Michigan KJ, so lots of rust. 128K on the Odo. I've been dealing with the "50mph drone" that rumbles from 50 to 55mph. It stops when I let off the gas and I can get it to happen on-off just by tapping the gas. So as long as power is applied to the drivetrain at 50-55mph it rumbles. I'm 90% sure it's in the front. Not like the 40mph growl from the rear diff on my other daughter's '02 limited. Based on everyone's advice: 1. New drive shaft U-joints, packed the spline with grease 2. New front Drive shaft, CV joints 3. New aluminum wheels_ Balanced BFG tires 4. New NGK plugs yesterday ..Nothing.......same rumble at 50. Bought but have not installed yet: Bilstein 4600's all around OME 926 and 948's New rear upper and lower control arms (originals super rusty) Dynaflow 2.5" exhaust/muffler (original super rusty) ......the above not expected to solve the rumble, just the ride I have not found any thread on this forum that provides an answer to the rumble issue. It seems it is very common. What do I try next?