HISTORY OF THE CHEVROLET TRUCK
First Generation 1960 - 1966
The 1960 model year introduced a new body style of light pick-up truck that featured many firsts. Most important of these were a drop-center ladder frame, allowing the cab to sit lower, and independent front suspension, giving an almost car-like ride in a truck. Also new for 1960 was a new designation system for trucks made by GM. Gone was the 3100, 3200, and 3600 designations for short 1/2, long 1/2 and 3/4-ton models. Instead, a new scheme would assign a 10, 20, or 30 for 1/2, 3/4, and 1-ton models. Since 1957, trucks were available from the factory as 4-wheel drive, and the new class scheme would make this known. A C (Conventional) in front of the series number would indicate 2-wheel rear drive while a K would denote 4-wheel drive. Actual badging on trucks still carried the series name system from the previous generation. The 10, 20, 30, and 40 series (C or K) were badged as "Apache", etc. 50, and 60 series trucks were badged as "Viking", and the largest 70, 80, and 90 series models were marked "Spartan" etc. in 1960, C/K trucks were available in smooth "Fleetside" or fendered "Stepside" versions. GMC called these "Wideside" and "Fenderside." Half-ton models were the C10 and K10 long-bed and short-bed trucks, and The 3/4-ton C20 and K20, as well as the one-ton C30, were also available. GMC did not use the "C" nomenclature, though their 4x4 versions had the "K" designation. GMC Model numbers for 1/2, 3/4, 1, and 1.5 ton were 1000, 1500, 2500, and 3000. The 1960,1961, & 1962 model used torsion bar front suspension, with trailing arm suspension rear. Trim lines were base and "Custom." Engines included the base GMC 305 in³ V6 for the GMC version, 135 hp (101 kW) 236 in³ (3.9 L) and 150 hp (112 kW) 261 in³ (4.3 L) straight-6s, and a 283 in³ (4.6 L) V8 with 185 hp (119 kW). A coil-spring front suspension came in 1963; along with a new base engine, a 140 hp (104 kW) 230 in³ (3.8 L) I6, and an optional 165 hp (123 kW) 292 in³ (4.8 L) I6. The cab was changed for 1964, with elimination of the "wraparound" windshield and a new front grille design, along with various interior changes. Air conditioning and a 220 hp (164 kW) 327 in³ (5.3 L) V8 came in 1965. A new base engine finished the model in 1966 with a 155 hp (116 kW) 250 in³ (4.1 L) I6.
Second Generation 1967 - 1972
A new, more modern look came in 1967, along with a new nickname: "Action Line". It was with this revision of the C/K truck that General Motors began to add comfort and convenience items to a vehicle line that had previously been for work purposes alone. The majority of 10 and 20 series Chevrolet trucks from 1967 to 1972 were built with a coil spring trailing arm rear suspension, which greatly improved the ride over traditional leaf springs. However, the leaf spring rear suspension was still available on those trucks, and standard on 30 series trucks. GMC models came standard with leaf springs with coils springs optional; all four-wheel drive models (Chevrolet and GMC) had leaf springs on both axles. 1967 was the only year for the "small rear window" (RPO A10 offered a large rear window as a factory option). The standard drivetrain came with a three speed manual transmission and one of two engines; the 250 in³ straight six or the 283 cu in (4.6 L) V8. The optional transmissions were the four speed manual, the Powerglide and the Turbo-Hydramatic 350 and 400. The 292 six and the 327 in³ V8 were the optional engines. The 1/2 ton trucks came with a 6 x 5.5" bolt pattern, the 3/4 and 1 ton trucks came with an 8 x 6.5" bolt pattern.
In 1968, the 283 cu in (4.6 L) V8 was replaced with a 307 cu in (5.0 L) and a 310 hp (231 kW), 396 cu in (6.5 L) V8 was offered for the first time. The most visible change in differentiating a 1968 from a 1967 was the addition of side-marker reflectors on all fenders. Also, the small rear window cab was no longer available. The GMC grille was revised, with the letters "GMC" no longer embossed in the horizontal crossbar. Another addition was the Custom Comfort and Convenience interior package that fell between the Standard cab and CST cab options. In 1968, Chevrolet celebrated 50 years of truck manufacturing, and to commemorate, they released a 50th Anniversary package, which featured an exclusive white-gold-white paint scheme. Also in 1968, the Longhorn model debuted on 3/4 ton trucks. Featuring a 133" wheelbase identical to the one ton vehicles, it added an extra 6" to the bed. Longhorns, interestingly, were 2wd only; no factory Longhorn 4x4 was built. The 327 c.i. V-8 engine was enlarged in 1969 to 350 CID (stroke increased from 3.25 to 3.48) with a net horsepower rating of 195-200, depending on emissions package 255 hp (190 kW), 350 cu in (5.7 L). Along with the new engines came a new grille design for Chevrolet trucks and a more upright hood for both Chevrolet and GMC trucks. A utility variant, known as the K5 Blazer, was also introduced with a shorter wheelbase of 104 inches (2,642 mm). The GMC version, known as the Jimmy, was introduced the same year. Some internal cab changes were also made, most notably the switch from a hand-operated parking brake to a foot pedal, and a more modern looking two-spoke steering wheel with plastic horn button replaced the previous year's three-spoke wheel with chrome horn button. Also new this year were upper and lower side moldings, which added another two-tone paint option. These were standard on CST trucks, and optional in any other trim level.
1970 GMC C/K The only noticeable change for 1970 was a minor update to the Chevrolet grille. At first glance, the 1969 and 1970 grilles appear identical. However, the 1970s plastic inserts actually have highlights that break the appearance into six separate sections. The 396, while still sold as such, was enlarged to 402 cubic inches starting in 1970. Several changes occurred in 1971. First came another new grille design (the "egg crate") for Chevrolet trucks and black paint over portions of the GMC grille. Second, an additional trim package was introduced: the Cheyenne. On GMC models, this was referred to as the Sierra. These packages consisted mostly of comfort features — nicer interiors, more padding and insulation, carpet, chrome trim, and upper and lower side molding and tailgate trim. 1971 was the first year for AM/FM radios factory installed. Finally, the front brakes on all light-duty trucks were switched from drum brakes to disc brakes, resulting in much less brake fade under heavy use. While many prior C/K half-ton trucks had used a six-lug bolt pattern (6 x 5.5") for the wheels, two-wheel-drive models switched to a five-lug pattern (5 x 5" bolt circle) common to Buick, Oldsmobile, Pontiac, and Cadillac passenger cars. The 1/2 ton 4 x 4 retained the 6 lug bolt pattern. This bolt pattern would remain the standard through the end of the C/K series (along with the Chevrolet/GMC vans). Also, Chevrolet changed the 396 V8 emblem designation to 400 V8.
1972 GMC Sierra Custom Camper The 1972 models were virtually identical to 1971 models, with the only change being the rear view mirror was glued to the windshield instead of being bolted to top of the cab, and metal or vinyl-covered flat door panels were no longer available; all trim level door panels were molded plastic with integral armrests and wood grain inserts on Cheyenne and Sierra trim levels. For restoration, it should also be noted that the door and window cranks were slightly longer due to the molded plastic door panels, and the vent windows were now secured with a single screw on the inside of the door, thus differentiating it from the 1971 model year.
Third Generation 1973 - 1987
An all-new clean sheet redesign of General Motors' Chevrolet and GMC brand C/K-Series pickups débuted in 1972 for the 1973 model year. Development of the new third generation trucks began in 1968, four years prior to production in 1972, with vehicle components undergoing simulated testing on computers, before the first prototype pickups were even built for real world testing. 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. As a result, the third generation trucks are officially known as the "Rounded-Line" generation. Some people may refer to them as "square bodys", given that the trucks appear square-like when compared to more modern automotive design standards. GM's design engineers fashioned the "Rounded-Line" exterior in an effort to improve aerodynamics and fuel efficiency, using wind tunnel technology to help them sculpt the body. Third generation design traits include "double-wall" construction, sleek sculpted body work, flared secondary beltline and an aerodynamic cab which featured rounded doors cutting high into the roof and steeply raked windshield featuring an available hidden radio antenna embedded into the glass. 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 secondary beltline to complement the cab in addition to new wraparound tail lamps. 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. The wheelbase length was extended to 117.5 in (2985 mm) for the short wheelbase pickups, and 131.5 in (3340 mm) for the long wheelbase pickups. A new dual rear wheel option called "Big Dooley" was introduced on one-ton pickups, along with a new Crew Cab option on the 164.5 in (4,178 mm) wheelbase. Crew Cabs were available in two versions: a "3+3" which seated up to six occupants and "bonus cab" which deleted the rear seat and added rear lockable storage in its place. The fuel tank was moved from the cab to the outside of the frame, and a dual tank option was available which brought fuel capacity to 40 US gallons. 1980 was the first year that a cassette tape player could be purchased, along with a CB radio. The Rounded-Line generation ultimately ran for a lengthy 15 model years (1973–1987) with the exception of the Crew Cab, Blazer, Jimmy, and Suburban versions, which continued up until the 1991 model year.