What are some proven fluids for track/race use in a GM manual transmissions requiring Dexron III? The usual suspect always seems to be Red Line D4 ATF but I'm open to other options. Motul Multi ATF, Schaeffer 204SAT All Trans Supreme, Renewable Lube Bio-SynXtra ATF PLUS, and Amsoil SSS all look stout on paper but don't seem to be specifically marketed as having a focus on extreme usage, racing, etc.
Is something like Mobil Delvac 1 ATF worth considering? It has an impressive list of approvals and is designed for heavy duty usage...but doesn't list Dexron.
The hottest temp the transmission has ever reported to the Performance Data Recorder is 250 F while out on track. The car has a dedicated transmission cooler and I change the MTF based on Chevy's recommendation of every 15 track hours. Previous Blackstone reports on the GM fluid have always been fine except for viscosity being a touch low.
The factory MTF is GM 88861800 which is made by Petro-Canada. KV @ 40 is 34 cSt and KV @ 100 is 7.7, giving an [insane] calculated VI of 207.
Car in question is below.
Is something like Mobil Delvac 1 ATF worth considering? It has an impressive list of approvals and is designed for heavy duty usage...but doesn't list Dexron.
The hottest temp the transmission has ever reported to the Performance Data Recorder is 250 F while out on track. The car has a dedicated transmission cooler and I change the MTF based on Chevy's recommendation of every 15 track hours. Previous Blackstone reports on the GM fluid have always been fine except for viscosity being a touch low.
The factory MTF is GM 88861800 which is made by Petro-Canada. KV @ 40 is 34 cSt and KV @ 100 is 7.7, giving an [insane] calculated VI of 207.
Car in question is below.