Need Help - Can't find problem! URGENT

Hi everyone,

I need your help. I have a 2000 Olds Alero 3.4L. The car has been making a "humming" noise near the front end. It sounds a lot like the noise you hear when driving on rough road. It happens no matter what gear the automatic transmission is in. It changes sound with speed (most prevalent at 40 MPH). The sound also changes when I turn the wheel - it is worse when I turn left going down the highway and the nopise is less when I turn right. I have replaced the driver side wheel bearing, the dirvers side dive axel (I noticed the CV boot was leaking), none of this helped. It sounds like it is on the drivers side so I have not messed with the passenger side. (CV joints look fine on the passenger side). I pu the car on a lift and ran through the gears - there is a vibration (car shakes) as the tires speed up - but I can't tell if it is a tire or soemthing else.
I need to know what this might be - transmission? -Tire? -Passenger Hub? Please help.

feel your tire man and see if it level across or cupping to see if the problem is being caused from an out of alignment front end. rotate your tires to see if the noise goes away that would eliminate the possibility of a tire problem.

This certainly sounds like a wheel bearing issue not a CV joint problem. If you replaced the drivers side wheel bearing the passenger side is probably bad too. I suggest you replace that one as well. It is also possible that the wheel bearing you recently replaced is bad but doubtful. I would however, check to see that everything is properly torqued especially the axle nut and the bearing mounting bolts.

Sounds like you need to replace the right ft bearing.

I agree..it's the other front bearing.....

When I first started doing these, you take a road test, and damn if it doesn't sound like one side, when it actually is the other....

Jacking the car up and feeling for play isn't the answer either(but if it has play, should be replaced)....have seen one side with play, and the other with no play, and it was the side with no play that was making the noise....

Finally, I figured out, you put the car on a lift, and then put the vehicle in drive......hold one wheel and the other spins at max speed....use a mechanic's stethescope, and place it on one of the bolts to the bearing(usually 3).....then do the same for the other side......the loudest noise gets the new bearing......never had a problem after that....

See lots of guys diagnose the wrong bearing and then tell the SM that both were bad.....

Thanks for your response Tech II. I was actually having a similar problem with my car making humming and grumbling noises when turning right but lessened when turning left. I replaced the right front bearing but the sound didn’t stop. I did what you said and the front left bearing was much louder than the right, even though there was more play in the right front tire.
Thanks for your help.

My mechanic friend helped me replace the other front wheel bearing this weekend and it seems to have fixed the noise.

Asbennett if you haven't figured out what the sound is, my friend told me about this helpful resource. It describes some common sounds if you have a bad wheel hub bearing. http://connect.timken.com/symptoms-of-a-worn-wheel-hub-bearing