Way they explained it to me was they use a detergent based solution that doesn't harm any parts or seals, etc. They have a dedicated bay with a constant temperature of 65 degrees and it pushes through the system while a vacuum pump pulls the old stuff out. When we do a "regular" fluid/filter change only 40% of the old fluid is actually expunged. Their flush gets ALL the old out, torque converter, pan bottom, filter, etc. Then a second neutral solution gets any residual flush fluid out. Finally they install new fluid specifically for your make/model vehicle and give a 75K mile guarantee. These are guys I've done business with for years and the first time I talked to Dan I said " GUARANTEE ?" He said yep. We'll replace your entire transmission and cover Towing or other costs if our system fails in any way. But now I gotta put a disclaimer here. These are guys I know. Somebody else, somewhere else may or may not go to all that trouble. Total cost for my other truck that had it done... $189 out the door. 2002 Chevy Silverado. I totalled it on the way to a 12:30 am Roadside call. Got blinded by a Jack up rig oncoming and head on into a parked car facing the wrong way on a residential street. That was Nov. 17th last year had surgery for a broken shoulder Dec. 1st, bought the Ram Dec. 6th and was taking calls again December 10th.