1990 C/K 1500 454SS
In 1990, Chevrolet introduced a high-performance variant of the GMT400 under the Super Sport emblem called the454SS. It was available only as a 2WD half-ton regular cab short box in Onyx Black only with a garnet red interior. The 454SS was powered by a 454 cu in (7.4 L) V8 producing 230 hp (172 kW) and 385 lb·ft (522 N·m). A 3-speed automatic transmission (Turbo Hydra-Matic 400) and 3.73 rear axle ratio added to the truck’s performance. The axle itself is unique, being a 14-bolt semi-floating unit which uses standard Chevrolet 5 on 5-inch wheels—the only factory-produced 14-bolt axle with such a wheel bolt pattern. The suspension was also upgraded with 32 mm (1.3 in) Bilstein gas-filled shock absorbers, a 32 mm (1.3 in) front stabilizer bar, and 12.7:1 fast-ratio steering gear assembly.
Unique exterior features included a front air dam with fog lights, special rims, decals displaying “454SS” on the bed sides, red trim emblems, and black painted grille, bumpers, and mirrors. The interior was also unique with a special plush Garnet Red cloth with black trim, high-back reclining sport bucket seats, and center console.