I believe in putting the rear tires up off the ground and let it run in gear, top off trans fluid, put a little pull on the kick down rod , let it go threw the gears, set the kick down then drive it to test, if the kick down is not hooked up low pressure will mimic a slipping trans, don't run it that way or it will eat those clutches and bands up.Well I discovered yesterday that the transmission in the dart is slipping. Unfortunately that is not something I can fix at my house due to the lack of space.
True this !!Torqueflites are pretty forgiving. Often times a fluid and filter change and tighten up the bands to sprc are all that's needed. Oh and make sure the kickdown is adjusted properly.