weird noises

[chemist]

I've got some weird noises coming out of the front of the Cobalt now. Anything above 35 MPH, and my wife describes it as a cross between a lawnmore and an RC airplane. I'm not sure what to make of it. I wonder if it's some sort of bearing growl... Anyone heard of this? Is there some technical service bulliten out there on it?

Some more background. I recently did the front struts. Also there's been this rattling sound going over potholes--struts really didn't fix it....

But this noise over 35 MPH has me REALLY concerned. What could it be?

Edit:
* It does it with or without my foot on the gas.
* It doesn't seem to have anything to do with braking or turning
* The noise changes slightly in pitch when you are going faster--I liken it holding cards to a fan blade at different fan speeds...

 

[ACE]

I've got some weird noises coming out of the front of the Cobalt now. Anything above 35 MPH, and my wife describes it as a cross between a lawnmore and an RC airplane. I'm not sure what to make of it. I wonder if it's some sort of bearing growl... Anyone heard of this? Is there some technical service bulliten out there on it?

Some more background. I recently did the front struts. Also there's been this rattling sound going over potholes--struts really didn't fix it....

But this noise over 35 MPH has me REALLY concerned. What could it be?

Edit:
* It does it with or without my foot on the gas.
* It doesn't seem to have anything to do with braking or turning
* The noise changes slightly in pitch when you are going faster--I liken it holding cards to a fan blade at different fan speeds...

lol if it was a honda i would say it was your motor.

sry im not helpful

 

[mrsilent13]

sounds like a bearing...i would say its an inner shaft bearing as it only does it with speed...

 

[outtamymind]

could be timing chain tensior. can't tell you for sure without being there. is the noise coming from the left side of the motor?

 

[G5tunerguy]

could be a bearing the rattling however did u check ur lower control arm bushings?

 

[chemist]

Update. The noise actually was a bearing growl. It was the passenger front wheel bearings. Replacing the wheel hub assembly mostly fixed the issue. Now, if GM had allowed us to simply greasepack the bearings ourselves every so often, I doubt these would ever fail... I've never seen bearings go on a car this new, and I've never seens bearings go inside of 70K miles...

It was easy enough to change. Two tips:

* For the top bolt, the only thing that fit in there was the back end of a 15mm wrench.

* Once all the bolts are removed, the only way to remove the wheel hub was using a hammer on the back of it. And, don't use a gear puller on the drive axle spindle/stud--it doesn't work and may f-up the drive axle...

As for the brake rotor--I had posted about that earlier, I had to unseat it by removing the old wheel hub, propping the rotor on wood then smacking the wheel hub with a 10# sledge. Nothing prior to that worked (heat, pb blaster, pry bars, smaller hammers, etc)...

Edit: The rattle over potholes was the control arm bushings, so to the guy who said that, good call. The lawnmore was the bearing. GM must have put a nickel and dime feature in these cars to activate upon warrenty expiration...