Let see if anyone can guess this noise!

When I'm driving a constant speed on the freeway or city streets (35ish) I have a humming type noise coming from the car. I can't identify ifs its coming from the front or back it seems to be coming from the entire car. Its not related to car speed, it sounds the same at 35 as it does at 65. When it starts at 65, if I slow down the hum doesnt change. When I'm on the freeway if I hit the brakes fairly hard (hard enough to make the nose dive)the noise will stop for a while. I know its not tire noise, because it does it on all different street surfaces - and its not related to speed. I tried rolling the windows down driving by a wall to see what it sounds like on the outside of the car, but I couldn't really hear anything. I'm stumped - it doesn't sound like any noise I've heard before from any car. This is my only week in town before I have to take off on another business trip (I put 3-4K per month on the car just for work)so I have to figure it out.

 

Maybe a wheel bearing.

 

I was thinking that, but I'm not sure how to check the bearings. I did find a bad bushing on the front passenger control arm and the drivers side rear caliper had siezed up and was getting really hot - must have siezed on Friday becuase I just peeked at the pads a week before to check them. I'm wondering if the siezed caliper could be causing the noise because it doesn't seem to make the noise until after its been driven for a while, I'll have a newcaliper and padstomorrow and will find out. The bushing is just making a clunking noise - thats next.

 

Hey now,

A high pitched squeeling when in motion will indicate a bad wheel bearing. A pull to the steering wheel, left or right, will indicate a bad caliper.

[sm=icon_cheers.gif]

 

One way to check for a bad wheel bearing is to see if the noise increases or dcreases when turning a corner, changing lanes, etc.... Try that and let us know if the noise changes.

 

The noise was the same at any speed, but I think I figured it out! I mentioned the drivers side rear caliper was frozen, the outside was frozen with the piston out most of the way so that pad was barely metal to metal (but no rotor damage yet) and the inside piston was frozen in all the way so that pad was barely touching the rotor. Between the two pistons frozenin different positions, it must have been making the noise - I drove about 20 miles after replacing the caliper and no noise. The car also pulls to the side when accelerating, but I also found a bad bushing on the front passenger side control arm, thats my next project.

 

Glad you found it