Quiet As A Mouse
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Pro
Joined: Feb 2016
Posts: 711
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Quiet As A Mouse
Since owning the car a few years ago I posted on the Forum that I had a slight sometimes groaning noise coming from somewhere in the rear when shifting my M7 into first gear. Well about 3 months ago I decided to have my Dif oil changed just to see if it would help. I put Mobil 1 gear oil in did not want the GM stuff. I was told by my dealer mechanic that Royal Purple or Mobil 1 gear oil was far superior to the GM stuff. Well just a ride or two later noise was totally gone forever no matter how I shifted. No, my Dif was not low on oil from the factory it was full. Just a heads up to anyone having a similar situation with the M7.Sometimes you get lucky.
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From: In a parallel universe. Currently own 2014 Stingray Coupe.
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Good that switching brands of gear oil has taken care of the noise. Much better than a major repair.
Melting Slicks
Joined: Dec 2014
Posts: 2,788
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From: Central UT
Glad it fixed your issue!! Just for kicks, I googled to see who produces gm gear oil. If this is the oil, it appears it produced by a Chevron company. https://cglapps.chevron.com/msdspds/...&docFormat=PDF
