I have removed the pan again and to oring and filter were correct, Fluid level was right where it should be. When in reverse i could not push it backward. Neutral it would roll back. Is there a possibility that this valve body is bad? Not sure if a bad valve body would cause no reverse or not.
Did you also check at the top side of the valve body? There is a port connector that has a thick black tapered, (Top) neoprene gasket. It connects to the 2 - 4 piston directly. If the gasket is torn or missing that might bleed enough pressure to prevent reverse. Otherwise, you may just have a defective body assembly. This is not the first dealer part of this kind that was junk from the box.
Just trying to remember all the things that can cause this fault.