Servicing AOD trans. Dextron VI or Mercon V?

[Sparky]

I will need to service my AOD soon. Not sure what the PO used for ATF. The dipstick says Dextron II. I read a post on another forum that made a convincing argument for Mercon V and said that Dextron VI is not backwards compatible.  Here is the thread:

https://www.ford-trucks.com/forums/1625085-1986-5-0-aod-transmission-fluid-dipstick.html

Right now I'm leaning towards Mercon V.  What do others use?  Also, I believe the torque converter does not have a drain plug. Should I not worry about the fluid in it?  Thanks

[ratdude747]

Dex/Merc is what I used last time... Mercon V is good too if you can find it (but isn't strictly required unlike in later applications). Do not use Type F or Mercon LV!!!

Specifically I bought 3 gallons of Valvoline Maxlife Dex/Merc. The TC does in fact has a drain plug... hidden between flexplate bolts (there's a cutout in the flexplate for it).

I think it took 10 quarts with the TC drained.. so 2.5 gallons, but it was cheaper to buy 3 1 gallon jugs and only use half of the last than to buy 2 1 gallons and two separate quarts. Gotta love bulk walmart pricing.  

[Sparky]

I just called a Ford dealer and they recommend Mercon V so that is what I will go with.

Good to know that there is a drain plug in the TC.

[Sparky]

FYI, the label on the Valvoline Maxlife Dex/Merc says it is Dextron VI/ Mercon LV, so I think they are equal.

[ratdude747]

I think that's the stuff.

https://www.valvoline.com/our-products/automatic-transmission-products/maxlife-multi-vehicle-atf

Supposedly per their FAQ that is mercon V compatible:

https://www.valvoline.com/about-us/faq/system-fluids-faq

I don't have the containers any more (got used and tossed for old fluid, used the leftover jug on something else)... and I'm out of the country on business.