high pitched whine outside left window?

[Dave Thompson]

I am having trouble narrowing down the cause of a high whining sound that comes from the left rear side of my car. It usually starts after a left turn and then continues, stopping when I stop the car, then sometimes resuming immediately when I go again, sometimes not until I corner again. It is similar to the sound made by a loose belt or a fan rubbing on metal housing, however there is no change in the pitch of the sound with any change in engine rpm. It does change slighlty with changing road speed, but oddly the pitch seems to go up as I approach stopping, rather than down, although it is really difficult to know that for sure.
I have pulled the left rear wheel and examined the area for loose things like maybe the shield plate behind the brake disk, and other suspension parts. Can't find any obvious signs. CV joint was a suggestion I got from someone, or maybe wheel bearings? Any one who can shed any light on this will be appreciated and admired. Thanks

[Dave at Pelican Parts]

Hmmm....

Well, CV joints usually go click-click-click-click when they start to go. Wheel bearings usually start to roar. Both will change with road speed.

Since neither engine speed nor road speed seem to have anything to do with it, that would appear to rule out the common squeaks.

About the only guess I have is that you have a brake pad that is dragging on the rotor. Does the noise change when you hit the brakes? Does it change if you pull up on the handbrake?

--DD

[John Rogers]

About the only other thing is the speedometer drive gear in the rear of the transmission, could be loose? Have you checked the alternator to make sure it is tight? Could be moving when you corner since you said it sounded like a loose belt. Do you have an air pump, check those connections? Last thing would be to go to a large empty parking lot and try to recreate the conditions. Then stop the car, block the front wheels and jack up the car quickly with a floor jack, put on stands and after the wheels are up, put it in gear to see if the noise starts when you go into gear and release the clutch. Race cars do this to warm up the rear end and tranny and listen for unusual noises. Make sure someone is inside in case of an emergency. This might work since you mentioned the noise started back up after you stopped.

[This message has been edited by john rogers (edited 05-04-99).]

[jmcleod]

i had a noticable whine in a vanagon transmission which was the ring and pinion destroying itself. it was due to chips and pits in the gear faces. it was noticable upon acceleration and not upon deceleration because the "back side" of the gear faces were in contact. there was no directional dependence of the whine however. maybe you could check your trans fluid level, if gears not covered in oil they could be making noise

[Dave Thompson]

john rogers wins the door prize on this one. After $34 diagnostic which took two days at a local foreign mechanic's, (who incidentally prescribed new rear wheel bearings at BOTH SIDES, $760, OUCH!!! as the probable solution) I found that my recently repaired odometer/speedo had stopped, and upon inspection, my angle drive gear had given up the ghost. Upon reflection, the logic of this is stunningly simple. Left turning had shifted the gear unit to the right and the resulting misalignment of the angle gears caused the whining. My dad, a mechanical engineer, confirmed the logic of this, too. The clincher was when the L shaped portion of the unit actually fell out and dragged on the ground: no more whining noises! Now I just need to get the new unit. Meanwhile, my cable is held up by a cable tie to the rear trans/muffler hanger bracket until I can give Tom a call... Thanks to all who volunteered suggestions on this. I really wish I had just listened to john rogers from the start, thanks john