Originally Posted by mikecote24
old thread but maybe someone will see this. I have a sound coming from the back almost like a tire rubbing but its not. Its not a clunking.it gets loud when you get to about 15mph and gets louder the faster you go. Putting it in neutral doesn't make a difference. i have no play in the tires but i havent ruled out wheel bearings. When i have it jacked up and someone puts it in drive the noise is pretty much gone. Does that mean i can rule out pinion bearings because thats been what i was thinking. Any suggestions? thanks
Just some general info on bearing noise:
Pinion bearings have a high pitch noise (because the pinion gear rotates faster than the carrier). Drive the vehicle and put it under load, if the noise occurs the source is the rear pinion bearing. If the noise occurs while coasting then the front bearing is the source.
Worn carrier bearings usually produce a low pitch noise that is usually present constantly and varies only with vehicle speed.
Axle shaft bearing can produce vibration and noise that will change when the bearings are under load. To check, drive the vehicle and turn sharply to the left and right. This will load one side and unload the other. The noise on the side that is under load will increase, conversely, the unloaded side noise will decrease or go away. When the damage is slight the noise will usually not be noticeable at speeds above 30 mph.