DT-51791 is a set of two adapters that thread into the 8L90 transmission front cover. The front cover must be removed to begin internal component service of the transmission. The cover has an O-ring seal that takes a set after repeated thermal cycles due to vehicle use and there is no surface on the transmission case that allows leverage and damage-free prying of the cover to remove it. The male ends of the DT-51791 Adapters are a 3/8-24 fine thread that fits in the cover holes. The female side of the adapters thread onto the previously essential J-6125-B Slide Hammers. Two slide hammers are needed to ensure an even pull so the cover does not tilt and become wedged in the case.