I think I hurt my diff clowning around off road last weekend. I could hear this sound on the highway home from camping that sounded like a cessna plane was in the distance, and its gotten louder and at lower speeds I can hear it. It seems to go away when I decel and is loudest when cruising. Ive checked all the tires and there is no irregular wear or cupping that could make this sound. How do I locate the source of the noise? Im thinking put the back up on stands and have my roomie run it up to about 60 while I get my stetoscope on and start probing??? Any ideas. Could I have hurt my driveshaft steady berring climbing over stuff, do I even have one? I did climb over a log that was in the path, but i dont remember hearing it hit the bottom except the front skid plate going either direction over it.