My 2005 Cavalier 2.2 4dr LS started to sound like it had a failing front axle bearing at 120K miles, so I replaced both sides with good-quality parts. But the old bearings didn't feel loose or noisy or actually any different than the new ones, and the noise at road speeds is still the same. The tires are evenly-worn about half-way, not cupped, and the rest of the frontend seems tight and solid. The noise can only be described as bearing-like, or maybe similar to using snow tires. No clunks, no whines or mechanical sounds, just a whirring sound. Anyone have some ideas? I haven't jacked up the rear yet to see what those wheels feel like.

 

I would put the front tires on the rear and the rear tires on the front to see if there is any change.

 

I drove the car over several different road surfaces and the noise remained the same, so I doubt it is tire related. The sound begins around 30mph and gets steadily more pronounced up past 70mph. It is a mechanical whirring drone-type sound that does not vary going around turns or with suspension movement--it is only speed-related. If I hadn't just changed both of them, I would swear it was a front axle/hub bearing. (The ones I replaced felt just as snug and quiet as the new ones) It doesn't get loud enough to drown out conversation, but is always present and annoying. What else in the driveline could cause such a noise?

 

Today I lifted the rear and spun each rear wheel, certain that one would be rough and noisy...but they're not! Now what?

 

We just had our 05 Suburban rear axle bearings done - even mechanic thought noise was coming from the front when he drove it. Nice and quiet again. Spinning rear wheels probably won't reproduce unless you get them up to speed. Years ago my 68 El Camino rear axles got noisy. Mechanic put it on a lift and had me run thru different speed ranges while he listened with a stethascope

 

I tried riding in the back seat listening and am quite sure the noise is NOT from either of the rear hub bearings. Then I swapped front tires side-to-side and again, no difference--the noise is still the same. Jacked car up on stands and ran it in gear...and no noise. I'm stumped--it's up to you smart guys!

 

I took the car to a shop today where they put it up on a lift to run the front wheels up to highway speeds, which I was nervous about doing on jackstands. There was absolutely no bearing noise, and they spun up the rears, too, and they're quiet. Since the sound does not change with different road surfaces, that seems to eliminate the tires--and this was a tire shop, so they would be inclined to recommend tires if they thought it necessary. SO, what now? Shop thinks could be a developing transmission issue, but said they couldn't check the level of the automatic transmission fluid because of no dipstick??? Car shifts fine and doesn't leak any ATF on the garage floor.

 

auto trans? the trans fluid can be checked with the engine running and the check plug removed. the shop isn't familiar with the transmission and took zero time to refer to service information. the shop could have easily listened to the transaxle when the vehicle was running on the hoist. take it to a dealership that has a qualified tech familiar with this car.

for giggles...post me a high def pic of the treadwear on each tire.

post a video of the sound.
bearing growl, diffs whine.
does the noise change in pitch or sound level when the car is swayed left and right or hard accell or decal?

 

You're right--it was annoying they didn't listen to the trans while on the lift to see if they could isolate the noise--after determining it wasn't hub bearings. Tires have been examined for cupping or uneven wear and they're fine, and none of the typical bearing-test moves like swerving right or left elicit any change in the steady pitch of the noise, which only varies with car speed. Does not seem to change when transmission shifts, either. I'm going to check trans fluid level anyway, now that I know how to do so, but am currently suspecting the alternator could be making a bearing noise. Will check that with a sound probe next. A/C on or off makes no difference.

 

an alternator bearing would make the noise with the car stopped engine running

did it make any noise when run on the hoist?

I hear you..the tires are fine....do you know what toe wear looks like and where to find it? its different than cupping and its commonly missed.