the pumper is probably getting ready to fall off.
those cars had aluminum backing supports behind steel bumpers, bolted to steel bumper brackets.
this introduced the public to bi metallic corrosion. 2 dis similar metals bolted together with no protection between the 2. corrosion between the 2 caused them to fall off the car.
it was a common sight back in the days to see these cars driving around with no rear bumpers. especially in the rust belt.