t79z28

Hey guys sorry to only post when I have a problem but this car is becoming a project more then I intended lol its a 99 z28 m6 has a faint whine only when going around 40 or faster at a constant speed. When I speed up or even blip the throttle it goes away but when my speed is constant it hums...is this just the song of its people? Or am I looking at a rebuild along the way? The car has 151xxx on the clock a lid and catback, I use it to cruse around an occasional 2 or 3rd gear pull.

you can hear it good at about 11 sec in, I was in 4th going about 40
https://www.youtube.com/watch?v=0Dfr...ature=youtu.be

Thanks for any help you guys really know your stuff, love the f body and this car has been nothing but good to me, and I plan to keep it that way

ramairetransam

iTrader: (18)

probably needs bearings , check out tick performance

t79z28

something like that is the tranny still good? This is my first manual and I learned to drive standard with it could my lack of skill have caused this? Been driving it for about a year, when I got it put a new MC slave clutch and pressure plate all OEM stuff

dgcustomz

iTrader: (127)

Are you sure its not a rear differential noise traveling forward?

t79z28

I'm pretty sure the diff was just rebuilt last week and uncovered this noise lol and it goes away whenever the clutch is pressed in

murphinator

iTrader: (2)

the diff is not under load when the clutch is pressed in its just rolling. You said when you go on and off the gas the sound goes away , classic rear diff noise symptom there , maybe get someone with something you can use as a stethoscope when it makes the noise and isolate the sound back by the diff or at the trans ? section of hollow pipe/tubing with a good ear to it lol maybe somewhere on the rear floor pan near anything that mounts to the rear , control arm bracket , spring pocket ,etc... or maybe just on the rear most part of the trans tunnel or under a removed rear seat bottom , I am thinking carpet would deaden the sound so probably not a carpeted area .

Car under load on a lift making the noise would be best but not everyone has access to one without first accessing their wallet

t79z28

ok deff something I'll try to do, I have a machine shop I trust alot to help me. But he's not free lol. Going to try a visual inspection first see if something is obviously wrong w its back end. If not I'll yank out the seats and stuff my friend in the back w a stethoscope. I'm assuming if the noise is louder at the rear its the diff? More towards the middle its the trans? The diff has a warrenty just don't want to grenade it doing 70 on the highway

SS_TOR

sounds like it's your rear diff