1999 with a DTT built auto with maybe 125 k on it total miles 150 k. Good transmission. Love it. Was expensive but worth it. I have a mag hi tech pan installed with a drain plug. Over the years I let the truck set for a week to let the torque convertor drain down. Then I drop the pan and change the gasket ( cork) and filter reinstall then add about 9 -10 quarts of atf plus three and a can of red lubeguard. I do this on a creeper in my garage .i have got pretty good at it and it's working well for me. So I'm doing about a half of the atf fluid . change out . My question is can I start the truck minus the 10 gts of fluid let it run a bit then shut down pull the plug And get more fluid out of the transmission or do you think I risk damaging the transmission doing that. I would like to get more old atf fluid out would be the goal.