Originally Posted By: thescreensavers
Generally you disconnect the supply line put it in a bucket. Then you get new ATF and pour it in the same time as the car is pumping it out at idle. Once the fluid coming out is new turn off engine reconnect lines and verify levels.
You may need a helper.
It isn't possible to pour it in as fast as it pumps. I do it w/o a helper like this.
Once you have the pan full of clean fluid:
a) pull cooler hose, put in a hose barb and hose extension led to a 1 gal. milk jug positioned where I can see it from driver's seat.
b) Run it until the milk jug is 3qts. full. You need to turn it off at 2/2.5 qts to make up for it spinning down.
c) add 3qts.
d) repeat b+c until fluid is coming out clean.
e) reconnect hose, run vehicle and adjust fill. The lost extra fluid from lines should leave you a little low so you can top-up instead of being overfull; or just slightly underfill after your last drain.
f) use leftover atf to do PS system flush.
This is what it looks like, though on this vehicle I have a drill pump to do the fill since it lacks a dipstick to pour it in and to make checking level easy (never again will I buy a vehicle with no AT dipstick!):
I spread around some cut-open lawn bags to catch fluid, and that makes clean-up A LOT easier.