Red Line 75W90, 17k mi OCI, 126k mi, Cadillac CTS-V

Apr 9, 2013
Philadelphia, PA
All mileage is in kilometers not miles. Notes from oil slip: "mostly regular driving in all seasons including harsh winter in northeast US and Canada plus more winter autocross driving events." Next fill is Red Line 75W110. Previous fill was Red Line 75W90 (same as this one).

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I noticed in engines sometimes the first uoa of redline is bad..esp on an engine that has higher miles...
So at first thought maybe its cleaning or suspending crud that was already there... but this is your second run of redline and gear oil so.... blah?

The 75w110 seems a good choice from this UOA.

Have you considered trying redline shockproof? If you are autocrossing it often?
It has a diff. oil cooler installed? Maybe get some temp monitoring on it? Any ideas on what temps it is running?
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This is the 4th fill of Red Line 75W90 for the diff.

AFAIK Red Line Shockproof (all grades) has issues in freezing winter temperatures with gelling. Let me know if that's not correct.

The diff oil cooler has a thermal switch that triggers it on when the oil temp is 180F or higher. I also sometimes run it manually when I'm on a longer trip just to make sure it gets run once in a while.