Wheel Bearing or Bad Rotors??

O.k. my truck started to make a noise and I think it is one of these two. I get a humm while driving. It just started a yesterday (or that is when I noticed it). It is kinda low pitch but constant. I am getting a little vibration in the steering wheel when braking (which is why I thought "rotors".) How do I check the wheel bearings? Suggestions?

 

On my cars that had warped rotors it was only detectable under braking, if you weren't braking you wouldn't know they were bad. To check your wheel bearings jack up the front and grab the top and bottom of your tire and wiggle. If there's any play your wheel bearings are probably shot.

Does the pitch change as you speed up? Does the pitch change when you're turning? If it's a bad wheel bearing get it replaced ASAP. I've seen some pretty nasty pictures of wheel bearing failures.

 

The bitch, er, uh, pitch doesn't change. It is just a tone or two below the sound of the CAI. I will try jacking it up tomorrow and wiggling the wheels. I appreciate the tips.

 

Could also be 'cupped' tires.

 

True but I rotate regularly. Not sure. Just started yesterday, kinda freakin me out. Only does it up to about 65mph then I don't hear it.

 

+1 Had the same thing. A humming noise, slightly worse while turning, then while braking. Wife got 200 miles away before it got bad enough she didn't want to drive it. Turned out to be the wheel bearing. Had to replace that AND the pads as the rotors/pads kept trying to hold the wheel straight. That cost me around $600 to fix. Catch it soon before it's more!

 

Terrific!! Trying to get an appt. quickly.