I know I've read some good info on similar problems here, but I was hoping for advice if I can be as specific as possible. There is a roaring sound from the back of the Jeep when I go over about 25 mph. It's loudest at 45 mph and decreases at higher speeds. I can feel a slight vibration of it in the steering wheel, and if I take my foot off the gas, the sound and vibration go away. I've had the jeep for about a year and have drven it this way for about 14,000 miles, without much change. The fluid level in the differential is fine.