1991 fj80 transmission fluid

[lumberjack]

Ok after reading about past transmission posts for the last two hours. I wanted to make sure that I could do this. I have a 1991 fj80 with what I assume to be a A440F trans. with 240K on it. It calls for dextron II fluid in the truck manual, but would it be beter to run Mobil 1 synthetic oil in it. Just wanted to make sure I was reading the posts correctly.

 

[sdbrassfield]

The main objective is to keep the fluid clean and fresh reg or syn. Syn will give you the upper hand on heat and heat transfer and fluid breakdown. I use Mob1 syn on all my fluids, trans, engine oil and gear oil, and grease....

 

[Cruiser Jimmy]

LJ,
I have not heard of any problems with Syn tranny oil.
I have personally used the Dex II with no problems.

 

[Jason Andrews]

Atf

If you don't want to go the synthetic route, or Mobil 1, Id go for the Valvoline Maxlife ATF.

 

[lumberjack]

someone was saying on another post that valvoline will thicken up at colder temps. Not sure if that really makes a bid difference or not.
Thanks everyone for the quick replies

 

[Russ in California]

Any additives?