Req'd Maintenance??

I have been on the search for the right ATF for my 2002 Tacoma V6 4x4 DC. My 2002 Toyota Tacoma's owner's manual says to use Dexron II/III. My Toyota dealer sold me Toyota ATF T-IV, saying it is backward compatible to Dexron II/III, but they are wrong, and I returned the Toyota ATF. I investigated this ATF issue as my local Toyota parts dealer, YouTube channels, and Tacoma forums recommend various ATFs. The most popular ATF is Valvoline's Max Life Synthetic ATF, as it's relatively inexpensive and easily available. Here's what I found. General Motors (GM) invented automatic transmissions and developed automatic transmission oils, later called automatic transmission fluids, to prevent people from using motor oils in their automatic transmissions. GM created various ATF fluids, including Dexron II/III ATF, to be used in various automatic transmissions, including Aisin automatic transmissions.

I found this on another website: "All DEXRON®-III licenses expired at the end of 2006 and were not renewed. GM does not license or support obsolete ATF specifications or the use of fluids marketed against canceled specifications. After that date, automatic transmission fluids sold in the market bearing claims such as “suitable for use in DEXRON®-III applications” or similar wording should be avoided. DEXRON®-VI licensed fluids are fully backward compatible and can be used in all applications covered by earlier GM ATF specifications. The use of unlicensed fluids and/or non-GM approved aftermarket additives detrimental to transmission performance and void warranty coverage."

When you read the Valvoline Max Life ATF label, it's NOT a GM licensed and not GM-approved ATF to be backward compatible with Dexron III. DEXRON®-VI is backward compatible with Dexron III. Valvoline's Max Life ATF is their formulation for various automatic transmissions, but it's not a GM licensed ATF and not an approved OEM ATF. See YouTube video by Professor John Kelly. https://www.youtube.com/watch?v=xUFY0L_zFek

The good news is that Valvoline does sell a GM-approved and GM licensed DEXRON®-VI synthetic automatic transmission fluid, and so do other companies.