Auto Trans question- 80-90 wt gear oil usage

Hello-
1997 tacoma, 2.4 L, extended cab, auto trans, 125K miles.

80-90 weight gear oil was used when transmisson oil was was drained
(app. 2 qts) . Drove about 10 miles and then drained again (2 qts) and added Napa Dexron 3 ATF.
I was thinking about changing it again in about a week, but after cruising all over the web, it seems
like it might be a waste of time as 80-90 wt valvoline gear oil seems like a good use in trannies for some folks.

Does anyone have experience with this please?
More than likely I will drain again in a week. It is so easy to do.
Thanx
Michael
PS - will not get it flushed no matter what.

 

80w-90 in an *automatic* transmission? That's…surprising.

80w-90 usually runs in the 14-16 cSt range (100 celsius). Dexron-III ATF, by comparison, usually runs 7.4 to 7.7 cSt (also @ 100 celsius). You dropped something twice as thick (at or near max. operating temp) in your auto transmission as what it likely calls for. It called for water, and you added room temperature honey.


I guess if it *works* for you, great. I'm not recommending it for a couple of reasons. One, it's not what the manufacturer calls out and the kinematic viscosity is all wrong. Second, there are additives, friction modifiers and detergents in even generic Dex-III that 80w-90 GLI 4/5 doesn't have. I'm not calling you stupid (because maybe you know something I don't), but I am calling you brave!

 

You my friend just fawked up your transmission. Why on earth would you add gear oil to an automatic? Unless your drunk.

 

80w-90 is SO much thicker than atf fluid. I wouldnt think it would be a good idea. But like the other guys said maybe u know something we dont so this is an occasion for popcorn

 

I would ask this on bobtheoilguy forum (google it). From my understanding its bad, you should probably flush the thing (via the radiator atf cooling system). Search diy atf flush.

 

The same reason you'd put ATF in your coolant *cough Krazie cough*

You sure the people running 80-90 had AUTO transmissions? Cause that's about what the 5-speed MANUAL calls for (I think I put 75-90 in mine, not sure)

 

Go back and read his question.

 

You haven't read this thread yet have you?

http://www.tacomaworld.com/forum/2nd-gen-tacomas/33318-halp.html

You get the idea after the first page...