2009 Tacoma, V6

New to Toyota World. I have a 2009 Tacoma, v6, double cab, 120,000 miles, that I have had since brand new. No problems with this vehicle except the a/c control. My dilemma is I changed the trans fluid about 3 wks ago (drain and fill, approx. 3 qts first time) and used Mobil 1 Syn atf at the first drain and fill. I used Toyota atf ws (purchased from Toyota dealer) the next 2 drain and fills, total 6 qts. used. So I have used 3 mobil 1 syn atf and 6 Toyota atf ws. I found on the internet somewhere that Mobil 1 syn atf is not compatible for this truck. I plan to do one more 3 qt. (Toyota ws) drain and fill in the next week. Question: What problems have I created? No problems with the trans after this total drain and fill. I do not pull a trailer, but maybe once a yr. and it is normally a light load. I put about 5,000 to 6,000 miles per yr on this truck since retired.

 

Welcome to TW!

Most users use Valvoline maxlife or Toyota ws. I would double check specs for the taco and fluid. If it were to cause any issues, you would have already felt the effects. I do know that Toyota states dexron III fluids and Toyota ws are not interchangeable much like full synthetic vs synthetic blend engine oils.

That being said I just flushed and changed the filter and filled up with global transmission fluid without any issues.

 

Its mixed in now so only way to get it out is a full exchange at the dealer for about $250 or read DIY posts.
Dealer did mine and shifted better and converter lockup was firmer - just my opinion and many hate the dealer full exchange so up to you.