Hard vibration, increases with speed. Not wheels.

[mylemonalero]

Have a 2002 Alero 6 cylinder sedan.

We've gone through the laundry list of common problems (even managed to fix the 10 minute security light issue) with the vehicle and had it running fairly smooth for about a year.

Recently there's been a heavy vibration at speed. Replaced spark plugs, brake pads/rotors. Took it in for new tires and alignment. Still happening. It seems to be around the front driver side wheel. There is no squealing though which, from what I've heard, seems to be a symptom of a hub bearing problem.

Any suggestions as to what might be the culprit? No warning lights on the dash. Could it be the CV joint? Or is it possibly the hub bearings without the noise?

The best way to describe it would be for every 5/6ths it sounds normal but the last sixth there's a bump. If I drive slower it happens slower, faster more frequent, but always with that sort of interval.

Any ideas/suggestions would be appreciated. Thanks.

[thusted]

Since nobody has replied, I'll give you somethings I have checked when trying to diagnose noises/clunks. I am not an expert, just someone who has been trying to work on my own car.

when you are at speed and hear the noise, shift into neutral and coast. If you continue to hear the noise at the relatively same frequency and intensity, the problem is in the rotating things (wheel bearning, break rotor/stuff, axle joints etc....)

If the noise reduces quickly when entering neutral, the problem is engine related.

If the noise is rotational. At speed, turn slightly left or right and see if the noise intensifies or reduces. Also, does the noise reduce or intensify if you hit the brakes?

Does the noise sound different on different pavements (like concrete, asphalt or stone/dirt) if so, might be a broken belt in the tire or a tire severely out of balance.

if possible, get an observer to listen to the car when you drive it by. I've found it valuable when trying to diagnose which side and front/back problems.

Hope this helps.

Todd