I have a 1995 SC2, automatic, with about 151,000 miles on it. When I get above 40mph I hear a whining noise that seems to be coming from the passenger side front. I've only had the car about six months. Since I've had it I've replaced the both front rotors, pads, both control arms, rack and pinion, serpentine belt, idler pulley, and belt tensioner. The whining noise occurs when driving straight. I haven't noticed if it gets louder when turning. Any ideas what may be the cause would be appreciated.

 

Does the whining change if you are on or off the throttle? In other words, if you are going down a hill, is it louder,quieter, or the same as if you're going uphill? Also,does it seem to match the speed of the car or of the engine? The two things that come to mind are wheel bearings,or a whine coming from the final drive of the transmission once it shifts into high gear. I have an Ion, and these noises can be really tough to find. I finally tracked mine down using a set of chassis ears. Turned out the noise was coming from the opposite side of the car it sounded like it was coming from!

 

Try rotating the tires. Oh, and do you have hub caps and maybe missing one or do you have alloy wheels on the car? A missing hub cap can cause some strange noises too.