There is a way to do a more thorough trans flush yourself...you'll need a helper for a couple minutes and that's it. And you can do this on just about any automatic that has a trans oil cooler.
My method:
1. Get the trans up to operating temp. Hot fluid does suck but it drains better.
2. Drop the pan, clean the silicone off both surfaces, wipe pan out, clean magnet off.
3. Change both filters, put the pan back on, add new fluid.
4. Unhook the cooler return line on the side of the transmission and stick a hose on the end of the line and run the hose to a 5 gal. pail.
5. I crawl under the truck and hold the hose with one hand and hold my thumb over the return line hole on the trans (so it doesn't suck air).
***If you do not cover/plug the hole it'll suck air and won't pump hardly anything into the pail***
6. I have my helper start the truck and let idle in park until the fluid just starts to sputter & holler to shut off the truck (this could take anywhere from 30 seconds to a minute or longer). If you've gotten at least 2 gallons in the pail skip to step #8.
7. Refill trans with new fluid again, and repeat #6 until you get at least 2 gallons in the pail.
8. Refill trans with new fluid again, and repeat #6, but this time have helper shift to Reverse for 5 seconds, Neutral for 5 seconds, and Drive for 5 seconds, then back to Park for 5 seconds, then shut off the truck.
8. Reconnect cooler return line, fill trans back up to proper fluid level, get up to operating temp, go through all your gears, and check for leaks.
I believe this method is the best way to do a system flush without using a dirty machine, and by changing the pan fluid and filters first you are not risking pumping any debris into the valve body or torque converter.
Take my truck for instance: a 68RFE trans holds roughly 17-18 qts total capacity. If you just do a pan drop & refill you are only replacing roughly 7 qts. That's not even half your fluid!!! Doing the method above will pump new fluid into the torque converter and pump the old fluid into the pail (min. 2.5 gallons) and ended up using 20 qts. So I wasted a couple brand new quarts but at least I did the job right
I've done this to my previous '05 Hemi 545RFE and it's the exact same. And the new TorqueFlite has a trans oil cooler so this method would work also. You just need to know which line is your return line. If you unhook the wrong line you'll be covered in red fluid.
If you're only dropping the pan at 50,000 miles & replacing the filters and half your fluid you really are just wasting money IMO.