Ford Crown vic

I have a 1989 ford crown vic with 5.0 motor auto trans, 80,000 original miles. Hardly even driven. The shifter will move from park to lo 1 fine, but when lever is in reverse car goes forward, lever is not lined up on nuetral when car is actually in nuetral drive and overdrive work fine, but car will not move backwards when lever is in reverse. Changed filter and fluid but still no reverse, yes but still does not move backwards when in reverse, but no reverse lights come on either. Thnxs