noise in rear
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noise in rear i have a stock 200ss z28 when makeing turns i get a thump thump noise sounds like th drive shaft is hitting the floor more noise when turning with no load on drive shaft left or right turns no play or leaking from axles no play in u joints pulled drive shaft u joints look and feel ok. also no sign of drive shaft rubbing or hiting, please help
Last edited by gmrench; Nov 15, 2018 at 12:30 AM.
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Sounds like pinion bearings have failed.
But could also be your positrac. An auburn positrac needs additive every so often. A torsen does not. So could be a binding clutch in the positrac if it's an Auburn. Cheapest solution is to add the additive first to see if that corrects the issue. It probably needs it anyway. If not then pinion bearings.
https://www.summitracing.com/search/...p-oil-additive
Assuming of course that shocks, panhard bar, etc are all connected and/or not loose or broken
But could also be your positrac. An auburn positrac needs additive every so often. A torsen does not. So could be a binding clutch in the positrac if it's an Auburn. Cheapest solution is to add the additive first to see if that corrects the issue. It probably needs it anyway. If not then pinion bearings.
https://www.summitracing.com/search/...p-oil-additive
Assuming of course that shocks, panhard bar, etc are all connected and/or not loose or broken
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here is some history on the car . it was my brothers he bought it new i was in the back set and heard the thumping when he made a turn he said that the noise was there from new , about a yr. ago he had the pinion seal replaced and the they must have over tightened the nut as 2 days after seal reaplacementl bearings went bad , was sent to a rear end only shop. they replaced all bearings but still made the noise on turns., now the car was given to me and it seems there must be something causeing this noise have checked all bolts and rear bushings new . sounds as if the drive shaft is hiting the floor but find no rub marks add u joints look and feel normal and have no bearing play. there is no noise ore wine when driveing it on freeyway on or off the gas pedal. just when turning noise is louder in turns with foot off the gas pedal. does sound or fell like the pos. is sliping think that it is factory thorsen type i will get under it again and check the pinion bearing . thanks.
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well pulled the cover found no chips or metal all bearings have no slop or movement what i can see of gears on axle look good un able to see all the spools would need to disamble it to check but before removeing do you know were to buy the spools and gears . could the noise just be the norm this type of rear end afer checking trans mount u joints all bushings are good no loosensss in pinion bearings or axle bearings etc.
A 2000 Z28 would have a Torsen posi,,a 2000 SS could have something else depending upon how it was optioned out at SLP. A pic of the posi would tell us.
Torsens aren't rebuildable, you can disassemble it but a special fixture is needed for reassembly.
Torsens aren't rebuildable, you can disassemble it but a special fixture is needed for reassembly.
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here is some history on the car . it was my brothers he bought it new i was in the back set and heard the thumping when he made a turn he said that the noise was there from new , about a yr. ago he had the pinion seal replaced and the they must have over tightened the nut as 2 days after seal reaplacementl bearings went bad , was sent to a rear end only shop. they replaced all bearings but still made the noise on turns., now the car was given to me and it seems there must be something causeing this noise have checked all bolts and rear bushings new . sounds as if the drive shaft is hiting the floor but find no rub marks add u joints look and feel normal and have no bearing play. there is no noise ore wine when driveing it on freeyway on or off the gas pedal. just when turning noise is louder in turns with foot off the gas pedal. does sound or fell like the pos. is sliping think that it is factory thorsen type i will get under it again and check the pinion bearing . thanks.
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it is a torsen. did not see any bad gears or spools that i could see. with cover off . sounds like the driveshaft is rubbing the flooronly on turns foot off the gas,bearings have nosign of wear axle bearing no exter play.first time i heard the noise i was in the back seat my brother was driveing he told me that the noise was there since day 1and has had no rear end problems hard to think that this is normal. i was a line tec . for chevy for 20 yrs then went to olds for 10 yrs. left gm in 1988. the ran a shop for boeing for 10 yrs,.lots fords.this is the first and only torsen i have seen. was unable to see all the spool gears . if it is a spool gear you just replace the complet unit?
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Lets see mine has 170k on it and has been making the "noise" since about 25k miles, forget about it. Long time ago I chased my tail trying to rid myself of the "noise" 2 grand later "noise" was still there. The torsen carrier is noisy once it has 20k or so miles on it. Either toss it out and go with a true trac or FORGET ABOUT IT.
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When a Torsen fails it makes a sort of clunk/click sound only when turning as the outside tire turns more rotations than the inside tire which is when the carrier has to spin its bits so to speak. The gear shafts that run parallel with the axles from side gear to side gear are very small and usually fail there or the teeth on the side gears that meet them. You can pull the carrier without having to reset any of the shimmed parts of the diff so long as you keep each sides bearing/race/shim organized. Then inspect the carrier closely and my guess is you will find something. If you want to take your chances and run it just be be prepared for a tow when those things let go they are done.
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Lets see I owned 6 f bodies equipped with the torsen................every one had the noise. They do break easy but that noise has nothing to do with it. Its the sound of the gearing unloading inside the torsen carrier. I always thought it was cool after I realized it doesn't mean a dam thing.