Hi guys,

I realize this may not be the best place for this thread, but I couldn't find a better one. I have a 2000 Z28 convertible.

I've noticed lately a high-pitched whining sound from my rear (right, mostly) wheel area as I approach speeds of 50-70mph.

It isn't the exhaust. . . but is more like a high(er)-pitched whirring sound. When I step off the gas, it doesn't change until I actually start losing velocity. It essentially disappears at around 45mph.

I had my tires rotated and aligned yesterday and asked them to check for anything wrong back there (bad bearing, etc.). They said it came up clean.

I hopped a parking lot curb with my right side about two weeks ago at about 20-25mph. Didn't even see it coming. Bang, bang as both wheels on the right side went over it. So, I'm thinking that this may have damaged something.

Well, I was just wondering if you guys had any ideas. I may take it into a "rear-end" guy here soon and I would like to have some theories for him so I don't sound too paranoid and/or clueless.

Thanks!

Hurin

 

Crap guys, I just saw the higher heading of "Powerplant Specific Technical Discussion" and realize now that this thread is even *further* removed from the topic of this board.

Oh well. Sorry about that. But if you have any ideas, I'd still be interested.

H

 

Well, that sounds like typical gear whine. It's usually a certain speed that will trigger the whine, and when you're coasting from a higher speed, it whines at that same "target speed"

 

Unless it whines all the time, its probably the usual par for the course gear whine like rncotton said above. Get a louder exhaust to drown it out.

 

Thanks for taking the time to reply guys. I guess I'll just try to ignore it.

The only other thing that has changed lately is that I let the oil change guys change my manual transmission fluid. Of course, I then looked in the owner's manual when I got home and saw that it isn't necessary.

But, of course, I wouldn't think this could cause gear whine! I mean, maybe if they changed the fluid in the rear axle, but not the transmission fluid. . . right?

Sorry to be so clueless, I love my car and wanted a Camaro since I was twelve. . . but I'm not as into customization and do-it-yourself as some. Maybe some day.

Best Regards,

Hurin

 

Hi guys,

Turns out that it was bearing noise with some accompanying noise from the differential. They're going to replace the bearing(s) tomorrow (glad I bought the extended warranty). While they're back there, they are also going to replace the rear differential because their "rear-end" guy said it was making quite a bit more noise than usual too.

I realize they might just be getting the most out of my warranty. . . and he said that they normally wouldn't replace a differential solely because of noise. . . but in this case, since they're already doing one, they're going to do the other as well.

Anyways, just thought I'd update this thread in case anyone ever hears anything similar.

H

 

Parts replaced. Noise gone. I'm happy.

 

Sometimes it pays to have an extended warranty......wish I had that for my rear end work!!!

 

I had an extended warranty, they didn't cover my rear when the pinion bearing failed and trashed the rear.

 

Well, a few days after I got the car back, it started to make a loud sound from the rear when I would turn/maneuver at low speeds. It was sorta a dull rubbing, oscilating, vibration sound. It almost sounded like a belt loose up front, but I gradually isolated it to the rear. I wish I could make the nature of the sound more clear.

Anyways, I took it back in yesterday, and they said that the problem was that more "additive" needed to be added to the rear assembly.

I have no idea what that means, but it hasn't made the sound since. My question is: Since I drove it for 2-3 weeks, did the *lack* of this additive do any long-term damage? The guy at the shop said "No, it's fine." But, ya know, some verification would be nice.

Thanks!

H

 

when you change the rear diff fluid you have to add the additive which cost about $6. as far as damage i doubt you did any damage since the noise disappeared once the fluid was added. i have this same/similar noise on both our 96 and 97 z28's and i have suspected the rear pinion bearing for some time. i replace the drive shaft twice on my 97 just to be sure it was not the drive shaft. i changed the rear diff fluid. i put new tires on it. i even replaced the rotors and pads. i still have the odd "rubbing/grinding" noise coming from the rear end. only thing left has to be the pinion bearing.

 

supposidly, if you have a Torsen, you may get this "rusty screw" sound.

I managed to frag my rear, so I got a stock replacment from another 3.42 M6 3 channel abs f-bod, and got a T2R diff put in.. got the shop to make sure everything was setup right.. I can't believe how much more solid and quieter it is than what I had before stock! Makes me wonder about how my old rear was setup..