I have had a roaring and vibration in the Jeep for a while and not it is getting louder. I checked the front wheel bearings and they are ok. The rear driveshaft doesn't appear to have any play. I jacked up the rear and noticed that there is noticeable play in each rear wheel. They don't have any up/down play but instead in and out. Is this normal? The Jeep is an 88 and bone stock.

 

In/out is normal for C-clip axles.

Did you check the front axle and drive shaft? (If 4x4) You may want to pop off the differential covers and have a look inside.

 

That makes me feel better. The front drive shaft has a fare amount of play but not in the u-joints. I really did not pay any attention to the front end since the vibration is coming back thru the steering wheel.