GMC introduced the second generation of C/K for the 1967 model year. The GMC C/K was an upmarket version of the Chevrolet C/K and was offered in light, medium, and heavy duty variants. As with the previous generation, four wheel drive variants were denoted by the letter K, while rear wheel drive trucks used a C. Variants offered were: C1500, C2500, C3500, K1500, and K2500. In terms of engines, a wide range of inline six, V6, and V8 powerplants were offered, as well were short or long box configurations. The second generation also saw the introduction of the Sierra and High Sierra option packages. The Sierra packages would eventually become trim levels starting in 1972. Production of the second generation C/K lasted until 1972, when GMC introduced the Third Generation C/K.