Hi all, I just got my 87 GXL this weekend and after a day of hard driving, I noticed a sound coming from the driver side front wheel. It was intermittant at first but ended up being more or less constant above 20 mph. It's a metallic sound for sure, but more high pitched than grinding. Brake pressure does not alleviate the sound. I hate to say it, but my guess is that the bearings are shot. My mechanical skills and tools available would probably limit me to replacing the entire hub assembly instead of taking my chances just replacing the bearings.

Does anyone have any suggestions on what to do? Any way I can diagnose it further? Recommendations on where to buy the hub? Mazda seems to want $500 I found one (5 lug) on ebay for $100, but it's from an S5.. is this part interchangable on the S4 and S5? Any help would be appreciated. Thanks!

My name is Carmine, btw.

 

Worn/damaged bearings usually have a growly-grindy kind of sound, not high-pitched. High-pitch could be something as simple as brake dust, which wouldn't necessarily go away with/without the brakes on. Jack up the front end and check for play/wear in the bearing by grabbing the wheel top and bottom and see if you an rock the wheel, independent of the suspension. It shouldn't move if all's well.
If there's no movement, you might try some anti-squeal spray for the back side (NOT THE ROTOR SIDE!) of the brake pads.