For 1991, the new low-cost W/T trim was release. The W/T was a stripped down fleet side, long bed, regular cab work truck…the 4.3L V6 and manual transmission were standard. A/C and radio were not! The 454 SS was also updated with an more powerful 255hp/405ft-lb 454 V8, 4.10 gears, and a 4 speed 4L80E automatic.

The 1990 model year featured a few exciting changes for the GMT400 Platform. The SS 454 package (RPO B4U) was released, combining the sport package with a host of performance upgrades including the L19 454 big block, 3.73 9.5″ rear differential, TH400 transmission, and suspension/steering upgrades.

The 1989 model year featured only minor revisions from the previous year. Pickup trucks still remained the only body styles available in the GMT400 platform.
Here you will find specifications and information for 1989 model year Chevrolet and GMC full-size trucks.
This includes engine ratings, drivetrain specs, and chassis dimensions.

For 1988, the fourth-generation Chevrolet and GMC C/K was introduced, including (1500) 1⁄2 ton, (2500) 3⁄4 ton, and (3500) 1 ton pickup trucks.
Here you will find specifications and information for 1988 model year Chevrolet and GMC full-size trucks.
This includes engine ratings, drivetrain specs, and chassis dimensions.