Originally Posted by Arod
Yeah it looks normal. nothin is loose. but a had a guy look at it and tell me that the gears might be to tight? backlash im assuming. and also could be a bad bearing.
Sounds like the common rear end whine that you get right before it grenades on you. The inner bearings go bad and it lets the ring and pinion come out of proper alignment. Or the gears are simply worn out. Depends on the mileage. I'd just scrap it. The reason you only hear it upon acceleration is because the ring and pinion having play in them now. As you get on the gas, the gears are loaded on one side of the teeth. As you let off the gas, the load is then transferred to the other side of the teeth because of decel from the trucks weight, tire friction on the road, etc.