Clarification requested on use of Redline MT-90 in rear diff.

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Apr 7, 2008 | 10:25 AM

bubba j

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Clarification requested on use of Redline MT-90 in rear diff.

If I take the search results at face value:

The transmission and front diff share 3 quarts of oil, and MT-90 is recommended for this.

The rear diff takes 1 quart, and takes 75w90. Since MT-90 is 75w90, and is commonly recommended for the front Diff/transmission, is there any reason I wouldn't use this in the rear as well?

Apr 7, 2008 | 10:32 AM

TTinCT

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nope....no reason.

Apr 7, 2008 | 10:34 AM

joe@vwvortex

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There was a huge thread on rear diff oil on Vortex in the R32 forum....

concensus was to use OEM in the rear diff. I honestly don't remember what the issues were - but you might want to do a search.

Apr 7, 2008 | 10:40 AM

Scenic Driver

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I thought the diff needed a GL-5 rated oil >>>

MT-90 is GL-4.

Redline 75W90 gear oil is GL-5 and Motul Gear 300 are GL-4/GL-5 rated.

Apr 7, 2008 | 11:04 AM

JohnLZ7W

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amsoil application guide for the TT shows the rear diff using GL4

<ul><li><a href="http://www.amsoil.com/scripts/runisa.dll?amsoiloaf.1636303140:RIGHTPANEL:4280319 39:TTQUA,AI,A,6038">http://www.amsoil.com/scripts/runisa.dll?amsoiloaf.1636303140:RIGHTPANEL:4280319 39:TTQUA,AI,A,6038</a</li></ul>

Apr 7, 2008 | 11:06 AM

bubba j

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Redline 75W90 NS

"This GL-5-type geal oil doesn't contain the friction modifiers for limited-slip hypoid differentials. This makes the transmission synchronizers come to equal speeds more quickly, allowing faster shifting and much easier low-temperature shifting. Can also be used in racing limited-slip differentials where weak spring design causes too much wheel spin. "<ul><li><a href="http://www.redlineoil.com/products_gearlubricants.asp?productID=47&subCa tegoryID=17&categoryID=7">http://www.redlineoil.com/products_gearlubricants.asp?productID=47&subCa tegoryID=17&categoryID=7</a</li></ul>