I have a whirring bearing noise in my 01 Tahoe. I thought it might be a pinion bearing, but now it might be a rear transmission bearing. I guess I'm going to have to take it to a shop and have it diagnosed. My drive line is tight at the differential, but I can move it back and forth a little at the rear of the transmission. Is that normal?

 

What you are describing is how most people describe a bad wheel bearing. It could also be the pinion bearing. Does it get louder when you accelerate and go away when you let off the gas? In my 12 years of working on car I have never seen the bushing ( it is not a bearing in the tail shaft) cause a noise like that.

 

my 2000 tahoe (5.7L old body style) is making a whinning noise thats louder when on the gas and gets quieter as you let off the gas and the vehicle slows. I have been trying to find its cause as well.

 

I hear a whinnig noise too on my 08 Suburban. All of the sudden, it seems like all kinds of things are going wrong with my truck, only 42k miles.

 

I had the wife drive the Tahoe past me at 25 mph and it sounds like its coming fromt he rear axel area...can it be my U joints? I have 165,000 mile on her and they are the original U joints. I did the "hill" test for the tranny. Pulled up on the side of a hill to a complete stop and released the brake, the tahoe slowly climbed the hill by itself.

 

If it whines when you give it gas and stops when you let off the problem is probably in the diff. Wheel bearings tend to maintain a constant noise whether on the gas or not. Check your fluid level - remove the fill plug and stick your finger in the hole. The fluid should be level with the hole. I just drained mine and added Mobile 1 synthetic 75-90w.

 

It was low (1/4-1/2" below the plug) but I filled it this weekend. Noise is still there. I wonder if the limited slip discs are toast?? It doenst completely stop till the truck stops..it just gets a little quieter when off the gas. Reminds me of running my 91 stang hard and holding 3rd gear too long and letting off the gas...similar whine.

 

I changed teh diff fluid but the issue is still there...from 20-25mph up I get a whine...if I let up the whine volume drops with the speed. It even makes the noise in N while going 40 mph. But as the vehicle speed drops the volume drops.