Whining sound rear end?

[1894]

2000 Explorer Sport with about 110k miles. I'm getting a loud whining/humming noise from the rear end. I can hear it on acceleration, cruising and deceleration. As I'm slowing down, the whine makes a winding down sound. I guess for that matter, it "winds up" as I'm accelerating also. I don't hear it at very low speeds, but it could still be there.

First noticed it after the tires were changed, but it doesn't sound like tire noise. Any suggestions on causes and how/where to get repaired? My mechanic recently retired, and I don't have anyone new yet who I trust. I'm worried about a big bill from someone who might not correctly diagnose and fix the problem.

 

[Cobraguy]

First things first. This definitely could be tire noise by the sound of it. Change the tires and see if it goes away. It started with a tire change...so that's where I would look. One thing to check is see if it changes pitch or volume on different road surfaces. Concrete, asphalt, etc.

Next, get it making noise, then turn the vehicle to the left, then right. does it go away or greatly diminish turning one way? If so, look at the axle bearing on the side of the direction of the turn. Right turn, right side, etc. If this isn't it, and the tires aren't it, you are probably looking at pinion bearings.

 

[1894]

Should have also mentioned that the vehicle seems to need brakes/rotors. I'm bringing it in for that. Any possible relation to the whining sound?

 

[Cobraguy]

Possible the pads are on the wear indicators I guess. But you would get a definite change if you applied the brakes.