The third generation of the C/K series is a range of trucks that was manufactured by General Motors. Marketed under the Chevrolet and GMC brands from the 1973 to the 1991 model years, this generation is the longest-produced version of the C/K model line. Adopting the "Rounded Line" moniker by General Motors, the third-generation C/K is the second longest-produced generation of American pickup trucks (behind only the 1972–1993 Dodge D/W-series Ram pickup).
Introduced as the successor for the 1967–1972 "Action Line" C/K trucks, the third generation C/K expanded its product range to a four-door crew cab pickup truck for the first time alongside the traditional two-door pickup and chassis cab trucks. As with the previous generation, the model line served as the basis for the Suburban and Blazer/Jimmy full-size SUVs and shared body commonality with GM medium-duty commercial trucks.
For the first time, GM marketed a generation of the C/K concurrently with its successor, leading the company to designate the third generation as the Chevrolet/GMC R/V for 1987. For the 1988 model year, the GMT400 chassis architecture adopted the C/K nomenclature for a fourth generation, with the R/V series ending production in 1991. Over its 18 model years of production, the Rounded-Line series of trucks (as the C/K and R/V series) were produced in multiple facilities across the United States, Canada, and South America.
From 1972 to 1991, the Rounded Line C/K trucks were produced in multiple facilities across the United States, Canada, and South America.
Source: Wikipedia
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Chevrolet Silverado. All pics are my own.