Diff oil temperatures

[terryobeirne]

DIFF OIL TEMPS.. Does anyone have an real data on oil temps they are measuring in a conventional rear drive diff???. I'm investigating diff oils for a mate (who has a diff overheating problem) and so far all the tech info is telling me the commonly found diff oils have a critical loss of viscosity (and thus load bearing capability) at 100C and some, a lot earlier. The standard SAE oil tests only assess the oil and 40C and 100C so there is a sparsity of published data in between these values. I would like to amass some real facts on what is being measured in real race cars, and them hopefully, look at possible solutions. FYI, I have a gear oil temp monitoring system on mine (transaxle), and after about 5 or 6 laps i'm at 100C and steadily rising to about 120C peak.
many thanks

[GORDON STREETER]

Originally Posted by terryobeirne

DIFF OIL TEMPS.. Does anyone have an real data on oil temps they are measuring in a conventional rear drive diff???. I'm investigating diff oils for a mate (who has a diff overheating problem) and so far all the tech info is telling me the commonly found diff oils have a critical loss of viscosity (and thus load bearing capability) at 100C and some, a lot earlier. The standard SAE oil tests only assess the oil and 40C and 100C so there is a sparsity of published data in between these values. I would like to amass some real facts on what is being measured in real race cars, and them hopefully, look at possible solutions. FYI, I have a gear oil temp monitoring system on mine (transaxle), and after about 5 or 6 laps i'm at 100C and steadily rising to about 120C peak.
many thanks

When I was racing the oval circuits I actually used to run an oil rad on the diff using a boat bilge pump to circulate it as the oil we used back then would actually boil in a long race and the crown wheel and pinions didn't last too long.
When later I was circuit racing using the newer synthetic gear oils with added ZX1 I never had a problem