Winding noise

[Lucion 81]

I have a 2003 GMC Z71 and at low rpm there is a winning noise I put in netruel wile costing reved up no noise pit back and ease in throttle and the winning noise starts again funny is that it is perfectly siinked with throttle when in gear and rolling but in n no noise on rev 

[dtnel78]

Check your U-Joints first. 

 

Checked the Trans or Differential Oil lately? Have you ever changed the oil in the Differential? If you can't find a U-Joint bad (Common) I'd move to the Differential fluid first. Open plug on side and if oil don't seep out or if you stick your pinky in and it don't get any oil on it at the first bend in the pinky then I'd get a gasket, oil from local parts house and change the oil out.

 

Pay attention to the oil as it's coming out and the bottom of the diff housing and the cover as well for any metal shavings, etc as this could indicate diff wear. Also I'd grab a few cans of Brake Parts Cleaner and a roll of shop paper towels, rags or whatever you use for wiping oil residue. I believe the oil types is 75W/140 but your local parts house can tell you for sure. 

 

Let us know what you find.