Hoping someone can shed some light on fixing a transmission slip issue. My 2007 Ford Taurus SEL has a reverse gear slip after driving for a while and fluid is hot. A little background... I purchased the car back in the summer. It has about 130K miles on it. I do not know if the slip problem was already there when I purchased but the previous owner says no. After purchase I replaced the trans pan gasket and filter due to a leak at the gasket. Refilled trans with Castrol Transmax Mercon V fluid. After that is when I noticed the slip in the reverse gear but only after the car is driven for a ways. When the car is parked for a while and trans cools off the reverse gear has good torque. Could probably spin the tires if I tried. As the trans fluid warms up the slip gets worse and worse to the point that it will slip on a slight incline. All forward gears work great. No problem with shifting through forward gears at all. Have thought about a complete fluid flush and replace but not sure that would help. Any help is greatly appreciated.