I got a old 76 F250 2WD camper edition w/ 390 engine, C6 tranny, a month ago. It's been highly modified, come with holley 4160 4bbl, eidelbrock per 390 manifold, vette headers, & etc. I'm repairing it little by little. yesterday, I found a pretty confuse thing, what type ATF that C6 is using? Type F or Mercorn? I've check both hanyes, chilton's and mitchell manual, all are diff. So, just see if some one know, or has owner's maunal. I hope it's Mercorn, since it's much cheaper than type F here. thanks

 

I found the answer on ATF dipstick: Type F for my truck.

 

You are correct. It is type F. My '76 C6 is the same. It is the only year of the C6 that takes the F type fluid I think.

 

77 up C6 uses Mercon, 76 down type F. I have no idea why the would be different. You would think a C6 would be a C6.

 

Welcome to the site


It appears you missed these 2 threads by a couple of days

https://www.ford-trucks.com/forums/s...d.php?t=509249

https://www.ford-trucks.com/forums/s...d.php?t=509632

Originally .....77 and newer uses DEXRON II then later on the 80's after it was introduced DEXRON III/Mercon

Mercon wasn't invented yet or on the market when these transmissions were made in 77.
BUT

that isn't saying that can't be used in the 77+ transmissions.
The Original application was Dexron II because that was the product that available and applied to the trans

Technology took care of that.

Applications:

Havoline Automatic Transmission Fluid MERCON®/DEXRON®-III is designed for use in General Motors Corporation transmissions that specify a DEXRON-III, DEXRON-II or DEXRON-IIE fluid and Ford Motor Company transmissions that require a MERCON fluid.

It is an excellent choice in any transmission where the manufacturer recommends a DEXRON® or MERCON® qualified product. It is suitable for use in Mercedes-Benz passenger car automatic transmissions and ZF truck transmissions. It is also recommended for transmissions, power steering systems, and hydraulic systems requiring a DEXRON®-III, Allison C4 or Caterpillar TO-2 fluid.

Havoline Automatic Transmission Fluid MERCON®/DEXRON®-III is also used as a light oil in compressors, pumps and hydraulic systems and bearings.

Always check your owners manual to determine the proper automatic transmission fluid for your transmission.

Ford transmissions manufactured after 1996 may require a MERCON V automatic transmission fluid.
Ford transmissions manufactured before 1977 and some pre-1982 transmissions require a Type F fluid such as Havoline ATF Type F.
Chrysler transmissions manufactured after 1996 require a Type 7176® fluid such as Havoline Automatic Transmission Fluid ATF+3®
Havoline Automatic Transmission Fluid MERCON®/DEXRON®-III meets or exceeds manufacturer’s performance requirements for:
General Motors DEXRON®-III
Ford MERCON®
Allison C4 Fluid
Caterpillar TO-2
Hagglunds-Denison HF-0
Vickers Pump
Voith DIWA Transmissions


Castrol Dexron III / MerconFormulated to meet the demands of today's electronic transmissions requiring superior fluid flow under low temperature conditions.
Key Benefits
Friction modified to provide improved durability and to ensure smooth transmission operation over the life of the vehicle.
Provides excellent high temperature protection, effectively resisting fluid oxidation.
Approved, certified and recommended by General Motors for all passenger car and light duty truck automatic transmissions.
Meets the anti-shudder performance and sprag gear wear requirements of the DEXRON®-III specification.
Suitable for use in applications calling for DEXRON®, DEXRON®-II, DEXRON®- IIE, DEXRON®- III and/or a MERCON® fluid.
Approved and certified by Ford for all 1983 to 1996 model passenger car and light duty truck automatic transmissions calling for a MERCON® fluid.
May be used in other hydraulic applications calling for a DEXRON®, and/or MERCON® fluid, such as power steering and shock systems.
Recommended for Chrysler and foreign car and light trucks calling for DEXRON®III or MERCON® transmission fluid.
Meets Allison C4 requirements.