x100 on maxlife being perfectly fine to use in these 4runner & tacoma transmissions.... a big thing people are confusing is that toyotas statement to only use WS fluid was when maxlife & other "universal" fluids were fairly new & not very popular, they mean to not use a completely different fluid than WS... maxlife & other modern fluids that are RATED for WS are 100% compatible with & acceptable to use in these WS spec'd trans.
there is not one single proven failure or damage caused to a trans by using maxlife if its rated for that trans... that covers hondas, toyotas, GM & other makes. if a trans that was on its last leg or had other issues failed, you cant blame the fluid. a drain & fill or full exchange with maxlife in our transmissions wont cause any harm or issues. & actually its been reported that shudder issues were improved or fixed when changing to maxlife, its states on the bottle it has very high levels of anti shudder additives in it, probably more than standard WS. use it without worry or use WS, the key is to change it at the intervals toyota recommends, which is 100k miles or 60k miles if used for towing or abused.