As everyone knows the Dexron fluid normally used by GM has a slipping agent, GM has never rccommended the type F because it doesn't contain the slipping agent, which Ford forever has recommended and shifts more solid. I've run Type F for over 40 yrs, in both racing and street cars and i've mixed them. I don't buy the special oils just OTC and i never use an additive like seal savers or anything else. I've tried the B&M and saw no difference from OTC's. I do use The VR1 in the alcohol engines, otherwise it's just OTC's.
JMO
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