GM Truck Generations: 1967-1972

06/01/2021

GM Truck Generations: 1967-1972

06/01/2021

Chevy C10/GMC K10 Second Generation


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. Updated styling features for the 1967 Chevy Pickup trucks came with new body sheet metal that helps fight rust and a pickup box made of double-walled steel. 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. The front suspension on all Chevrolet trucks was independent front suspension with coil springs. 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, while the 3/4 and 1-ton trucks came with an 8 x 6.5″ bolt pattern.


1968 Chevy C10/GMC K10 Differences


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 it, 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 4×4 was built.


1969 Chevy C10/GMC K10 Differences


The 327 cubic inch V8 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 a plastic horn button replaced the previous year’s three-spoke wheel with a 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 Chevy C10/GMC K10 Differences


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.


1971 Chevy C10/GMC K10 Differences


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 Chevy C10/GMC K10 Differences


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 the 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.

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