
Dex/Merc Transmission Fluid
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- The Dog House
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Dex/Merc Transmission Fluid
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! 

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
1979 Starcraft 14' Rowboat with 2011 Mercury 9.9 hp Outboard
Former boat: 1971 Trojan F26
- prowlersfish
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Re: Dex/Merc Transmission Fluid
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 .
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat

- The Dog House
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- Joined: Mon Jan 09, 2012 6:51 am
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Re: Dex/Merc Transmission Fluid
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
1979 Starcraft 14' Rowboat with 2011 Mercury 9.9 hp Outboard
Former boat: 1971 Trojan F26