there is a neat little option built into the valve body so that if someone were to try and put car into reverse when it was moving forward at 25mph[i think]the lever will not move past neutral[bingo you just saved your trans]this consists of a valve with a solid steel plunger that pops out of the secondary valve body when set speed is reached and then goes back when slowing down below 10mph.unfortunately this is accessed by removing the trans pan and first taking down the valve body and then removing the big plate with the secondary valve body on it.you will have to dissassemble the reverse safety valve and clean out the dirt that is causing it to stick[yes dirt] while you are there good idea to remove small v/body from plate and clean out the filters for the govenor[they will be in the underside of the small v/body.one more thing replace the main plate gasket as you go back together.[the original is probably ready for the smithsonian] by the way the reason you can move the lever when engine shuts down is because no more pressure from front pump.david poole european performance dallas tx.