Strange Humming Sound From Right Rear Of Car

[topichka]

Hello,

I have an 01 GS430 with 123K miles. I've had this very subtle humming noise that comes from the right rear of my car. I thought it was my tires but I had them replaced this last weekend and the noise is sitll there. It's not that loud, but increases in volumne slightly between 40-50 miles per hour. It's most noticeable when I'm in a sweeping left hand turn, around 40 mph. It doesnt' seem to make the noise when I turn right. I thought it might be my wheel bearings but the guy at the tire shop said he put it up on the rack, turned the wheel by hand and couldn't replicate the noise. Then I thought it might be the rear diff. so I took the car out, drove until I could hear the noise and shifted into N, but the noise didn't change at all.

The car is out of alignment--I can't feel it but when I took my old tires off, the front right tire was basically bald in the outer edge. Could this be an alignment issue? I'm not the most mech. inclined so any help will be greatly appreciated.

Thanks, Brian

[anthonyiez]

most wheel bearing noises are impossible to recreate on the rack, unless the bearing it really bad. i would be inclined to say the bearing is going bad because when you shift the load, via turning right, the noise goes away. one way to check it while loaded is to drive the car nice and hard, make sure to keep shifting the load, then use an non-contact thermometer to check the temp of each rear hub. if one of the bearings are bad it will read higher.

[topichka]

most wheel bearing noises are impossible to recreate on the rack, unless the bearing it really bad. i would be inclined to say the bearing is going bad because when you shift the load, via turning right, the noise goes away. one way to check it while loaded is to drive the car nice and hard, make sure to keep shifting the load, then use an non-contact thermometer to check the temp of each rear hub. if one of the bearings are bad it will read higher.

Thanks for the info. I appreciate it.

[SKperformance]

Very true ,any good tech would know the bearing needs pressure to make the grinding noise. A rotating wheel would make no noise in the air unless it was about to fall off.

[topichka]

Very true ,any good tech would know the bearing needs pressure to make the grinding noise. A rotating wheel would make no noise in the air unless it was about to fall off.

Thanks for the added commetns. Is this an expensive repair? I'm a bit ignorant when it comes to what something like this should really cost...

Thanks again.