The second-generation C/K, nicknamed the Action Line, was sold by Chevrolet and GMC for 1967 to 1972. For 1971 it got a mid-cycle revision, with blacked-out trim on GMC grilles and front disc brakes. GMC pickups used rear leaf springs as standard, the opposite of Chevrolet. GMC's 2500 series is the three-quarter-ton truck. Here we have a 1971 GMC C2500 pickup, with an automatic gearbox.