Ok, I've been reading thread after thread on the flush vs non flush here. I even contacted Toyota directly and they said "drain and fill" on my 01 4runner, 116K (drain and fill was done at 30, 60, 90K). I'm thinking I will do what I've done on my Honda (Hondas do NOT like flushing) and drain, fill, drive around for a few days, drain, fill, drive around a few day, and then drain, fill one more time. I know that doesn't get all new fluid in there, but it would get the fluid MOSTLY new.

I DO intend to drop the pan on the first drain/fill and clean it out, and I'm kinda sorta thinking about disconnecting the tranny line and putting all new fluid in there like the writeup on yotatech, but my main question is.....which fluid should I use? I know Hondas are pretty much ONLY supposed to use Honda fluid if you don't want your tranny to explode, but what about 4runners?

Is there a special "toyota" tranny fluid or can I use mobil1 or Castrol (I've always used Castrol GTX oil in my vehicles)?

If I were to use, say, Catrol ATF, would it mix ok with what is in there, or do I really need to do a flush and put all new stuff in there?

I just had mine done today ..."Drain and Fill" ..ONLY...if they've got over 100,000 on them, that's all Toyota says to do ....Mine is a '99 4 Banger with 124,000+ on it...

DEXRON III is what the Toyota dealership used...

Labor, parts, fluids, supplies all came to $42.75

Will have my wife's done on Friday - she's driving a '98 V6 with 144,000+ on it...

So does the brand of Dexron matter? Will any DEXRON III fluid be compatible with any other DEXRON III fluid?

I don't think there's a compatibility problem - the invoice on mine says "bulk", so obviously the dealership buys it by the barrel - as long as it says DEXRON III, I wouldn't be too concerned.