Just had the C-6 Cruise-a-matic transmission in a '66 Galaxie re-sealed at a trusted transmission shop. When done working on the transmission they refilled it with bulk Mercon fluid. I mentioned the dip-stick says use Type F fluid. They said not to worry, the Mercon would work just fine..The car drives fine with nice crisp shifts, just like before it was serviced..So is this an issue or not..?? I know the Newer fluids have different friction modifiers to promote a "softer" shift but in the old C6, I can't tell any difference, the shift points are firm and distinct as before. So why keep messing with type-F ?? Seems like the ATF section keeps getting more and more shelf-space...
Mercon and Type F, Is There That big A Difference?
- Thread starter Greasestick
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I'm paying attention because of you see no downside, I might do a flush in my 69 ltd with same transmission. I've always used type f in my old fords but maxlife would be nice to have on hand as a fluid for everything as trans and power steering fluid. Other than my civic power steering...
Originally Posted By: Greasestick
Just had the C-6 Cruise-a-matic transmission in a '66 Galaxie re-sealed at a trusted transmission shop. When done working on the transmission they refilled it with bulk Mercon fluid.
How many quarts did they use to refill it?
If they only used a few, it will probably work just fine. Had they filled the entire transmission with Mercon, you could have problems.
I'm not so sure I could call this shop "trusted". I suspect type F fluid is such a slow mover, they don't want it to take up shop space.
Just had the C-6 Cruise-a-matic transmission in a '66 Galaxie re-sealed at a trusted transmission shop. When done working on the transmission they refilled it with bulk Mercon fluid.
How many quarts did they use to refill it?
If they only used a few, it will probably work just fine. Had they filled the entire transmission with Mercon, you could have problems.
I'm not so sure I could call this shop "trusted". I suspect type F fluid is such a slow mover, they don't want it to take up shop space.
Back in the day we were told that we could run f in a trans that takes dex but never to put dex in a f trans
MolaKule
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How much M5 did they put in there and how much was already in there?
Inform those ignorant shadetrees that this transmission requires Type "F" and they will do a complete drain and refill with type F gratis.
Inform those ignorant shadetrees that this transmission requires Type "F" and they will do a complete drain and refill with type F gratis.
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Depends on if it was ever rebuilt or modified...
Crisp shift sounds like mild shift kit or mods making the transmission more immune to fluid type. Rebuilds don't always use OE clutch material making Mercon acceptable.
Is the transmission never rebuilt completely stock?
Crisp shift sounds like mild shift kit or mods making the transmission more immune to fluid type. Rebuilds don't always use OE clutch material making Mercon acceptable.
Is the transmission never rebuilt completely stock?
MolaKule
Staff member
Originally Posted By: Greasymechtech
Depends on if it was ever rebuilt or modified...
Crisp shift sounds like mild shift kit or mods making the transmission more immune to fluid type. Rebuilds don't always use OE clutch material making Mercon acceptable.
Is the transmission never rebuilt completely stock?
The OP didn't say it was rebuilt, only that the seals had failed and the seals were replaced.
What the shop did was out of laziness and ignorance.
Mercon V is NOT equal to Type F. Mercon V is a friction modified ATF, whereas Type F is not.
Ford needed a fluid that had a specific friction coefficient, because the clutch pack diameters were small in the Type 70, C4/C5 and other Ford transmissions.
In order to not create a lot of heat with these smaller diameter clutch packs, the pistons (actuators) had to force a quick clutch engagement, resulting in very "snappy" gear changes.
Any other fluid in these transmissions will eventually cause slippage once the wet clutche materials get soaked with the new fluid. Slippage causes overheating of the ATF (and oxidation) and accelerated wear of the clutch disks and clutch plates.
http://www.bobistheoilguy.com/forums/ubb...ion#Post1111352
Depends on if it was ever rebuilt or modified...
Crisp shift sounds like mild shift kit or mods making the transmission more immune to fluid type. Rebuilds don't always use OE clutch material making Mercon acceptable.
Is the transmission never rebuilt completely stock?
The OP didn't say it was rebuilt, only that the seals had failed and the seals were replaced.
What the shop did was out of laziness and ignorance.
Mercon V is NOT equal to Type F. Mercon V is a friction modified ATF, whereas Type F is not.
Ford needed a fluid that had a specific friction coefficient, because the clutch pack diameters were small in the Type 70, C4/C5 and other Ford transmissions.
In order to not create a lot of heat with these smaller diameter clutch packs, the pistons (actuators) had to force a quick clutch engagement, resulting in very "snappy" gear changes.
Any other fluid in these transmissions will eventually cause slippage once the wet clutche materials get soaked with the new fluid. Slippage causes overheating of the ATF (and oxidation) and accelerated wear of the clutch disks and clutch plates.
http://www.bobistheoilguy.com/forums/ubb...ion#Post1111352
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