in the car i just mentioned, the 93 Pro LX auto, the mechanic mentioned the tranny fluid was a good colour, but "oxidizing"

Should Im replace fluid, recycle, all at once, or a bit at a time?

help, Trannies make me nervous!

 

A complete flush would be ideal but most shops don't do that. Most will drop the pan, clean the magnets of metal shavings and replace the filter and seal. There is a bit left in the transmission even after a drain. Fill it up with Amsoil ATF. Mine's is beginning to make a sound like a blown bearing...It has me worried. Rebuilts are $1400.
Oh, and install a $25 tranny cooler for good measure.