Chevrolet C/K - GMC C/K (4th Gen) 1988-2000

Development of these trucks began around 1984 and were introduced in April 1987 as 1988 models (known as the GMT400 platform), there were eight different versions of the C/K line for 1988: Fleetside Single Cab, Fleetside Extended Cab, Fleetside Crew Cab, and Stepside Single Cab, each in either 2WD (C) or 4WD (K) drivelines. All C/K models would ride on independent front suspension. Three trim levels were available: Cheyenne, Scottsdale, and Silverado. Engines were a 160 hp (119 kW) 4.3 L V6, a 175 hp (130 kW) 5.0 L V8, a 210 hp (157 kW) 5.7 L V8 and a 6.2 L diesel V8. A 230 hp (172 kW) 7.4 L V8 was available in the 3/4-ton and one-ton trucks.

A drastic difference between the 3rd-generation and 4th-generation GM trucks was the suspension. The 4th-generation GM trucks used all independent front suspensions (IFS).

In 1989, a half ton 2WD fleetside Sport appearance package was available with black and red bumper and body trim, and a black grille with red outlined Chevrolet emblem, chrome wheels with custom center caps, and fog lights. The 89 was a limited production run set to determine how well the "sport" package would be received by consumers in the years to follow. The Sport package was more of a trim and towing package edition as well as a few engine enhancements that weren't on available on other Chevrolet trucks of the time.

Also in '89, the 4x4 sport appearance package included black bumper and body trim, wheel flares, mirrors, sport grille, 16–inch cast-aluminum wheels and special "4x4" badging on the box and "SPORT" badged on the tailgate. The box and tailgate decals were flanked by red outlined Chevy bowties. The sport package was only offered from 1989 until 1992 as some insurance companies began to express concerns with the idea of a high-performance truck. RPO code was BYP. This model was only available with the standard cab and regular fleet-side box. Colors included white, black, and red. A Z71 off-road package was also available with skid plates and Bilstein shocks making it the first off road package offered by the big three automakers and a few years later ford would make their own the FX4 package. The Work Truck (W/T) was also introduced in 1990, which featured a single cab long bed with Cheyenne trim and new grille with black bumpers. Also in 1988 the GMC 3500 EFI with a powerful 454 (7.4 L) was available. The 454 EFI produced 230 hp (172 kW) and 385 lb·ft (522 N·m). In 1991, the 4L80-E automatic transmission was available for the 3/4-ton and one-ton trucks. In 1992, the 4-speed manual transmission was dropped and the stepside trucks were available with extended cabs. The 6.5 L diesel V8 was also made available with a turbocharger. In 1993, the Sport package was available for the step-side models, featuring body-colored bumpers, mirrors, and grille with cast aluminum wheels. The 700R4 transmission was replaced with the 4L60-E automatic in 1993 also. 1994 models received a new front fascia, federally mandated CHMSL, many new exterior colors including a new two-tone option on the rocker panels, and new tire and wheel combinations. All 1995 models received a new interior that included a new steering wheel containing a drivers side airbag, a new dashboard containing a more central-mounted radio, dial operated HVAC system and an improved gauge cluster. New front door panels, and new seating were also included. The only interior bits not redesigned were the interior panels rear of the doors. Exterior changes this year included a special two tone faded paint job, available in many different varieties new gloss black folding exterior mirrors, and the door handles were changed from a smooth gloss black finish to a textured, satin finish. In 1996, a passenger side-mounted 3rd door was optional on extended cab models. A new range of engines were included. The "Vortec" engines meant HP increases across gasoline V6 and V8 smallblock engines. The 6.2 diesel V8 was dropped. 1997 saw a passenger-side airbag on 1500 models in order to comply with new federal regulations for light trucks. 2500 and 3500 models are exempt. This meant a slight dashboard redesign to incorporate these airbags. On models where passenger airbags weren't included, the space was occupied by a storage compartment. 1998 meant minor trim and badge updates as GM readied the end of the GMT-400 Platform. There was some overlap in 1999–2002 model years. In response to continued fleet sales the GMT400 trucks were produced as the Sierra Classic/Silverado Classic until the GMT400 ended production at the end of the 2002 model year. A Brazilian version of the GMT400 is currently produced in Brazil powered with a Chevrolet inline six.

The GMT400 and G-Van were the last two platforms to utilize the traditional small-block Chevrolet V8 in the 2002 model year.

The GMT800 platform was introduced in 1999 as the Silverado/Sierra.

[B]454SS[/B]

n 1990, Chevrolet introduced the first high-performance racing focused truck of the big three automakers a high-performance variant of the GMT400 under the Super Sport emblem called the 454SS. 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.

For 1991, a four-speed electronic automatic transmission (known as the 4L80E), 25 more horsepower, and even higher torque (405 lbs/ft at 2400 rpm) were added to the 454SS. The rear-axle ratio was also lowered to 4.10:1 for extra jolt off the line. On the dash was a tachometer, oddly omitted from 1990 models.

The MSRP of the 1990 model was US$18,295 with a $550 destination charge. A total of 16,953 units were sold over the 4 years the 454SS was in production, with 1990, the first year of production, selling 13,748 units alone. The 454SS was discontinued after the 1993 model year.

In 1992–1993 other color options included Summit White and Victory Red, with multiple interior colour options. The rear quarter panel and tailgate decals also changed in 1992 to a more 'stylized' 'SS' and the Chevrolet sticker on the tailgate became much smaller and located on the corner area.

[SIZE="1"]Source: wikipedia.org[/SIZE]