Part two for my ATF drain/fill questions...CD4E behind Duratec 3.0 with 150k miles. This will be very long, but please bear with me!
I bought unit with 106k miles, and a check of the fluids at purchase revealed bright red, new fluid. Tranny worked well...not perfectly, but pretty good. I have no idea what was used, but tranny calls for Mercon, not Mercon V.
After about a year and 25k-ish miles, had a partial drain and fill done by my CT garage b/c I couldn't get the tranny drain plug loose. According to the invoice, they used a generic multi-vehicle ATF, one that is good for both Mercon and Mercon-V applications.
After the change, the tranny didn't seem to work a lot better, a bit but not a lot. After another 6 months and maybe 10k, I did a drain and fill, and used ST Dex. III/Mercon fluid, and a bit of stop leak.
After THAT change, the tranny seemed to perk up and work a lot better. Just felt crisper and less 'sloppy'. From my research, it seems that Mercon V fluids are much thinner than DexIII/Mercon, and I've read many times that older CD4E's just work better on Mercon, even though they are spec'd for Mercon V.
So I'm fine with using older-spec Mercon, but I'd like the better cold flow and heat resistance of a synthetic without 'messing up' the tranny from a super-slick fluid. I just noticed Amsoil has put out an OE Dex/Mercon tranny fluid. It's 7.5cst, as opposed to the 5.8 cst for the Dex-VI/Mercon-V OE fluid. So it should not cause problems from thinness.
What do you think? Should I just stick to 'basic' cheap Dex/Mercon fluid in the unit that seems to work, or use the Amsoil syn fluid, that should be the same thickness as a mineral fluid, and may provide better protection? I wasn't consider a syn fluid, as most are multi-spec fluids, but this Amsoil OE stuff is strictly old Dex-III/Mercon spec'd stuff....
Sorry to ramble....love to hear thoughts now that this new Amsoil stuff is out....
I bought unit with 106k miles, and a check of the fluids at purchase revealed bright red, new fluid. Tranny worked well...not perfectly, but pretty good. I have no idea what was used, but tranny calls for Mercon, not Mercon V.
After about a year and 25k-ish miles, had a partial drain and fill done by my CT garage b/c I couldn't get the tranny drain plug loose. According to the invoice, they used a generic multi-vehicle ATF, one that is good for both Mercon and Mercon-V applications.
After the change, the tranny didn't seem to work a lot better, a bit but not a lot. After another 6 months and maybe 10k, I did a drain and fill, and used ST Dex. III/Mercon fluid, and a bit of stop leak.
After THAT change, the tranny seemed to perk up and work a lot better. Just felt crisper and less 'sloppy'. From my research, it seems that Mercon V fluids are much thinner than DexIII/Mercon, and I've read many times that older CD4E's just work better on Mercon, even though they are spec'd for Mercon V.
So I'm fine with using older-spec Mercon, but I'd like the better cold flow and heat resistance of a synthetic without 'messing up' the tranny from a super-slick fluid. I just noticed Amsoil has put out an OE Dex/Mercon tranny fluid. It's 7.5cst, as opposed to the 5.8 cst for the Dex-VI/Mercon-V OE fluid. So it should not cause problems from thinness.
What do you think? Should I just stick to 'basic' cheap Dex/Mercon fluid in the unit that seems to work, or use the Amsoil syn fluid, that should be the same thickness as a mineral fluid, and may provide better protection? I wasn't consider a syn fluid, as most are multi-spec fluids, but this Amsoil OE stuff is strictly old Dex-III/Mercon spec'd stuff....
Sorry to ramble....love to hear thoughts now that this new Amsoil stuff is out....
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