1985 Chevy C20 Scottsdale 5.7ltr V8 on 2040-cars

The C/K was Chevrolet and GMC's full-size pickup truck line from 1960 until 1999 in the United States, from 1965 to 1999 inCanada, from 1964 through 2001 in Brazil, from 1975 to 1982 in Chile. The first Chevrolet pickup truck appeared in 1924, though in-house designs did not appear until 1930. "C" indicated two-wheel drive and "K" indicated four-wheel drive. The aging C/K light-duty pickup truck was replaced with the Chevrolet Silverado and GMC Sierra names in 1999 in the US and Canada, and 2001 in Brazil; the Chevrolet Silverado HD and GMC Sierra HD heavy-duty pickup trucks followed. Until this time the names Silverado and Sierra were used to identify the trim level of the C/K trucks.

For the first Chevrolet C Series, made from 1911 to 1913, see Chevrolet Series C Classic Six, (the first Chevy).

An all-new clean sheet redesign of General Motors' Chevrolet and GMC brand C/K-Series pickups debuted in mid-1972 for the 1973model year. Development of the new third-generation trucks began in 1968 with vehicle components undergoing simulated testing on computers before the first prototype pickups were even built for real world testing.^[5] The redesign was revolutionary in appearance at the time, particularly the cab, departing from typical American pickup truck designs of the era. Aside from being near twins, the Chevrolet and GMC pickups looked like nothing else on the road.^[6] The third-generation trucks are officially known as the "Rounded-Line" generation.^{[7][8][9][10]} The "Rounded-Line" moniker highlighted the pickup's rounded-lines or rounded styling cues that were incorporated into the design. These rounded-lines included rounded windshield corners, rounded cab roof, sloped rounded doors which cut high into the cab roof eliminating roof height, rounded front fenders, and rounded pickup box corners which allowed for rounded or curved wraparound taillamps, a first for GM pickups. The design also featured strong distinctive curvedshoulderlines which rounded out below the beltline.^[7] The curved shoulderline continued across the back tailgate on Chevrolet Fleetside and GMC Wideside models. Some people may refer to this generation as "square bodies", although this nickname did not originate from General Motors and is thus, not official.

GM's design engineers fashioned the "Rounded-Line" exterior in an effort to help improve aerodynamics and fuel efficiency, usingwind tunnel technology to help them sculpt the body.^[11] Other design traits include "double-wall" construction, sleek sculpted body work, a aerodynamic cab with steep windshield rake, and a unique available hidden radio antenna embedded into the windshieldglass.^[7][12][13]

There were two types of pickup boxes to choose from. The first type, called Fleetside by Chevrolet and Wideside by GMC, was a "double-wall" constructed full width pickup box and featured a flared shoulderline to complement the cab in addition to rounded box corners and the new aforementioned rounded wraparound taillamps. Both steel and wood floors were available. The second type, called Stepside by Chevrolet and Fenderside by GMC, was a narrow width pickup box featuring steps and exposed fenders with standalone tail lamps. Initially, only wood floors were available.^[14]