GMC Jimmy I gallery (1970–1972)
The first generation of the full-size GMC Jimmy was introduced on the GM C/K truck platform with a fully removable fiberglass top.
The first generation of the full-size GMC Jimmy debuted in 1970 as GMC's counterpart to the Chevrolet K5 Blazer. Built on a shortened wheelbase of the GM Action Line C/K pickup truck platform (104 inches), the Jimmy featured a heavy-duty ladder frame and rugged truck-based underpinnings. Its signature body feature was a fully removable fiberglass hardtop, allowing the utility vehicle to transform into an open-air convertible cruiser. The Jimmy was offered in both rear-wheel drive (C-series) with independent front suspension and four-wheel drive (K-series) configurations utilizing solid live axles with leaf springs front and rear. Engine options included GM's durable inline-six powerplants (250 cu in 4.1L and 292 cu in 4.8L) alongside legendary Small-Block V8 engines (307 cu in 5.0L and 350 cu in 5.7L). Transmission choices ranged from 3-speed and 4-speed manual gearboxes to the 3-speed Turbo-Hydramatic TH350 automatic paired with heavy-duty transfer cases like the Dana 20 or New Process NP205. Marketed across North America, the first-generation Jimmy quickly established GM's presence in the booming off-road recreational vehicle segment.