What fluid to add

[mrjb9475]

Ok the previous owner said the fluid and filter was changed I do not know what fluid was used I need to add about 1/2 to 3/4 quart what should I add is it ok if I just use type F what if they didn't I do not know this is a 1970 lincoln

[Dan Szwarc]

This is a tough question to answer correctly. If you know the transmission has been rebuilt in the last 15 years, use dexron. If you have a low mileage car (under 50K) stick with Type F.

[TonyC]

Yes, that is tricky. As Dan suggested, many recent rebuilds would convert the transmission to use Dexron fluid, since GM had pretty much monopolized the transmission fluid standards (don't ask me why). It is very important to determine what fluid is in there; maybe a reputable shop with a lab can figure out which formula is in there.

In 1970, it's supposed to be filled with Type F originally; but if it had been rebuilt in the past, it is possible to use Dexron--in fact, the C-6s from '77 onward had Dexron. The C-6 can use either fluid, but not at the same time. Type F and Dexron have different formulas and do not mix; doing that will send your transmission into total surgery or the grave in short order.

---Tony

[mrjb9475]

It has 55,000 on It and was not rebuilt just told the fluid and filter was changed and this is evident because the pan is nice and clean and fluid looks good just a little low

[Dan Szwarc]

Just add some Type F.

The great ATF thread here basically says that Ford specified that Type F could be used to top off Type A (Dexron before Dexron was named Dexron).

This debate was never finally settled. Too many naming conventions were bandied about.

[jon schapiro]

Late to the game on this topic, but let me tell you my story. I was told by a transmission specialist in 1978 that I should change my type F to Mercon as it had a higher boiling point, and improved friction coefficient. I had him change the fluid to Mercon in 1978 and the car has been performing beautifully ever since.

[Lee]

I guess I’ll add my 2 cents as well: great success in my ‘62 with Mobil 1 Delvac Synthetic, meeting the Allison TES-295 specification. Total overkill along with a BIG cooler, but I’ve nursed this tranny for 100,000 + miles, no seal leaks, clutch engagement friction feels identical to Type F, and the fluid never gets brownish or burnt smelling.