No I don't and that's on purpose. I'd rather drain/refill vs completely swapping the ATF in order to NOT shock the transmission. If I had owned this rig since brand new, I'd have done complete empty/refill. I do this on all of my vehicles, including the DDs so that the ATF stay's clean-ish while still letting some of the brake/clutch band material float around in there.

I realize this is a highly debated topic - complete flush or drain/refill but this has been working out well for me for decades so I just continue on. Let's see this rig has 370k, which is the highest mileage on my driveway. Others all have 250k+ on them and no issues, knock on wood.

On a side note, my 1990 Benz has the ability to drain the torque converter, as well as the transmission pan so that one gets a complete drain/refill every few years. I wish all vehicles had this feature.

I always measure what comes out and put back in the same exact amount, which tends to be nearly one gallon of ATF out of all of my vehicles.

What folks don't realize is that when we're doing a fair amount of 4low grunt work, this REALLY heats up that transmission fluid. IMHO, you can't really hurt the tranny by doing too much drain/refills. Transmissions LOVE fresh ATF that is crimson pink with a sweet odor.

Those of us who are running larger than stock tires and DIDN'T regear, you should be doing frequent drain/refills as well. Due to the lack of proper gearing, you're pressing harder on that gas pedal in order to get those giant meats rolling. This translates to more effort on your transmissions.

Another side note, if you have a scanguage, look up the PID code and program that into your unit and watch that tranny temps. You'd be amazed at how quickly that ATF temp goes up and then goes back down. I tow a LOT so it's good for me to know that temp, although I don't live by it or anything. Just curious on how hot the tranny gets while towing up a steep trail in 4low vs 4hi. Even though the V8 has no issues towing my 2500# offroad camper, doing it 4low is so much better for the ATF because the fluid moves through the ATF cooler much faster. I have dinky tires so that helps out a lot in this regard.

Thank you for the link BTW @y=mx+b