Trojan Boat Forum

I've been using Pennzoil Dex/Merc transmission fluid in my transmission, V drive, and trim tabs. Pennzoil has stopped making it. What Dex/Merc transmission fluid are people using? Both the Pennzoil and Mobil 1 synthetic transmission fluids are supposedly Dex/Merc compatible. Are there any conventional Dex/Merc transmission fluids still being made? I feel like just when I learn the answers they change the questions!

I have never been picky on what brand of ATF I used as long as it was name brand and met specs . "Dex/Merc compatible" Compatible with never gave me a warm and fuzzy feeling so I try and find a fluid that meets specs . Per GM Dexron V is fully backwards compatible with any Dexron ATF and I have never had a issue with it in auto/trucks (and I use a lot) . BUT , in a boat I try to stick with Dexron III (lower # is fine ) . For now you can still get the dex III at most stores .

Castrol Transmax Dex/Merc has similar specifications compared to the Pennzoil (17,000 cP for the Castrol compared to 17,200 cP for the Pennzoil). These transmissions and V drives were originally designed to use Type A ATF (64,000 cP), so the higher cP the better in my mind. Mobil 1 synthetic ATF only has 10,000 cP, so I'll probably use the Castrol when I change my fluids in the Fall. Hopefully Castrol will keep making the Dex/Merc product!