Dex/Merc Transmission Fluid

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The Dog House
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Dex/Merc Transmission Fluid

Post by The Dog House »

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! :o
1993 Sea Ray 200 Overnighter OB with 1993 Mercury 150 hp Outboard
1979 Starcraft 14' Rowboat with 2011 Mercury 9.9 hp Outboard
Former boat: 1971 Trojan F26
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prowlersfish
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Re: Dex/Merc Transmission Fluid

Post by prowlersfish »

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 .
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The Dog House
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Re: Dex/Merc Transmission Fluid

Post by The Dog House »

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!
1993 Sea Ray 200 Overnighter OB with 1993 Mercury 150 hp Outboard
1979 Starcraft 14' Rowboat with 2011 Mercury 9.9 hp Outboard
Former boat: 1971 Trojan F26
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