I am trying to trace down a sound/vibration on the car.

I first thought that it was my front rotors. After changing them out, the sound is still there...but the brakes are much better.

The best way I can describe the sound is a bum, bum, bum, bum... sound that seems more noticable at slow speeds. It does seem to be rythmic and as speed increases, so does the frequency of the sound. The sound happens with the car in drive or neutral. Turning the wheel left seems to get rid of the sound/vibration. I have noticed it often when coasting to a stop, however it seems to quiet significantly or dissapear with brake application.

I would just swap the bearings, if it wasnt for the cost.

Am I on the right track or barking up the wrong tree?

Thanks much,
-Doug

 

Remove a wheel and replace a lug nut or 2 to cinch up the rotor against the hub.

Spin it and check the run out on the outside edge of the rotor.

My guess is that the thin metal guides the brake pads rest on are just touching the rotor.

If not, replace the wheel and grab it at 12 and 6 o'clock and see if you can make the tire wobble, pushing in at 12 and pulling out at 6 and then just the opposite.

Check for play.

I've gone through a bunch of hubs and never heard one. But I guess it's possible.

I'm sure you've already done this, but look for other silly things like a a tie wrap or even a brake line rubbing against a wheel or tire.

 

Thanks for the reply.

I have checked the rotors and I am sure there is nothing contacting them other than the pads. I did check for any play in the wheel, and there seems to be none.

The car does have 115K on it, so I am thinking about shelling out the $$ to replace both front hub/bearing assemblies.

Is there any other check that I can do?

Thanks
-Doug

 

Rotate your tires front to back. The front tires on our cars tend to feather on the outside, and this will give you what can become a rather loud wump wump wump sound most noticeable at low speeds, particularly on smooth pavement.

I've got $5 that says this is the problem, it's very common. It's also why I've never understood how guys run staggered tires.