sometimes my 1991 GMC sierra 5.7 doesn't wanna back up
it goes into reverse but feels like the brakes are on it will back up but gotta lay on the gas its like maybe???? the transmission valvebody is leaking pressure into another vessle and applying pressure to another band or clutch pack. and its fighting against each other. Problem is it goes away comes and goes, any ideas? i drive it regular just try to aviod parking so I have to reley on it don't wanna focce anything if I don't have to presently working fine