2002 Pontiac Montana whining noises

I own a 2002 Pontiac Montana van with 36,000 original miles. The past year it started making a loud whining noise that seems to come from the rear of the vehicle. It seems to be worse in summer than in winter. It iis really loud when turning into a parking lot or when turning sharply to go thru a drive thru at a restaurant. I have taken it to several mechanics and also to a dealership, and no one seems to be able to find the problem. Has anyone else experienced this problem with their Pontiac Montana van? I have no idea what to do about this situation. Can anyone help me solve this problem? Thank you.

Sound can move around and seem to be coming from somewhere other than its true source.
Have you tried opening the hood, having a friend turn the steering wheel, and listening for the source? Pay particular attention to the power steering pump. Whining when turning is a common symptom of failing PS pumps.

Post back.

Yes, others have experienced this problem. It’s apparently a rear differential issue with the AWD system. (If you don’t have AWD, then ignore this.)

The bulletin says that new differential fluid may help, but in severe cases the only fix is a new rear differential.

PS…it always baffles me when someone reports a “really loud noise” that no mechanic can seem to locate. Especially in a case like this, a loud whine from the rear that gets worse when turning is a classic symptom of a rear differential problem. Either the mechanics you took it to were deaf or they didn’t want to be bothered.

I was unaware that they made these in AWD. Is yours an AWD Bluedog?

Yes, my van is AWD.