Originally Posted By: tommygunn
Walmart Supertech ATF+4 is just as good as Valvoline ATF+4 and Mopar ATF+4 (which I believe is supplied by Valvoline) because it *is* Mopar ATF+4
You see, ATF+4 isn't just a spec.
ALL ATF+4 is the same!
Chrysler is such a control freak about this stuff. It's not just performance specs. Chrysler goes further and not only requires specific ingredients, they even specify the suppliers of those ingredients. A specific group III oil from either Shell, Petro-Canada, or SK. The only permitted add pack is from Lubrizol.
So whether you get Mopar from the dealer, or cheap Walmart ATF+4, it's all the same.
ATF+4 also a license that is about 15 years old; publically introduced in 1998, IIRC? Which also means that it was probably on the drawing board (so to speak) nearly 18 years ago ...
To put that in perspective, the API engine oil classification back then was SJ. We've seen SL, SM and now SN, all as Chrysler has hung onto "ATF+4" as their "premium" trans fluid. So, while it may have been an industry leading benchmark back in the day, it's no where near class-leading now. There are plenty of fluids that can outperform it, in a sense of what an ATF is supposed to do; many fluids that are not licensed to ATF+4 still lubricate, clean, resist shudder, resist oxidation, resist evaporation, etc, etc. Not for one moment do I think ATF+4 is some magical fluid that no other fluid could usurp. It WAS (past tense) a leader, but is no longer.
The concept of using both performance and chemistry criteria as a matter of license approval is not unique to Chrysler, either. Allison, for one, also does as such with their TES requirements. TES-295 approved fluids are some of the most robust ATFs out there for their application.
There are plenty of fluids that are licensed to this ATF+4 specification; I'm including both performance and content requirements in the term "spec" here. Any of them would make for acceptable use in the correct application. It's just that the least cost option that is licensed will assure the desired "spec" and return the better ROI. Therefore, there is no reason to believe that the ST ATF+4 is superior or inferior in daily use to any other ATF+4 product. It just probably costs less.