What year are the OBS Chevy trucks?
The OBS designation refers to Chevrolet's Old Body Style pickups built on the GMT400 chassis from model year 1988 through 1998, including Silverado and Sierra variants. This year span is what enthusiasts typically call OBS, with 1999 ushering in the New Body Style (GMT800).
Defining OBS: What makes these trucks distinctive
OBS stands for Old Body Style, a designation used by collectors and enthusiasts to distinguish Chevrolet’s late-20th-century C/K trucks from the later generation. These pickups share a squared-off, utilitarian aesthetic, a durable GMT400 platform, and were offered across light- and heavy-duty configurations (1500, 2500, and 3500). A visual refresh in the early 1990s refined the look but kept the same underlying architecture until Chevrolet shifted to the GMT800 platform for 1999 model year vehicles.
Model Years in the OBS window
The OBS window comprises the model years from 1988 through 1998, inclusive. Here are the years most commonly cited by enthusiasts.
- 1988
- 1989
- 1990
- 1991
- 1992
- 1993
- 1994
- 1995
- 1996
- 1997
- 1998
These years mark Chevrolet’s Old Body Style C/K line on the GMT400 platform, representing the popular OBS generation. The shift to the New Body Style began with the 1999 model year.
Notes on 1999–2002 vehicles
Starting with model year 1999, Chevrolet introduced the New Body Style (GMT800) for the Silverado and Sierra. While some casual references may label certain 1999–2002 trucks as “OBS” in conversation, the official designation for that period is New Body Style (NBS). Enthusiasts typically reserve OBS for the 1988–1998 range.
How to verify if a truck is an OBS
When evaluating a potential OBS vehicle, use a combination of model-year checks, visual cues, and official documentation to confirm the generation.
- Check the model year in the VIN: 1988–1998 corresponds to OBS; 1999+ indicates the New Body Style.
- Inspect exterior styling cues: OBS trucks feature the squared-off cab and fenders, traditional grilles, and specific bumper designs characteristic of GMT400.
- Look at the interior and dash layout: OBS interiors align with late-80s to late-90s design before the 1999 redesign.
- Confirm the chassis family on documentation or dealership records: GMT400 identifies the OBS generation, while GMT800 denotes the New Body Style.
Knowing these identifiers helps buyers, historians, and restorers accurately classify a Chevy truck as OBS and avoid mislabeling during restoration or sale.
Summary
In brief, OBS Chevy trucks are the Old Body Style C/K pickups produced from model year 1988 through 1998 on the GMT400 platform. The next generation—Model Year 1999 onward—introduced the New Body Style on GMT800. If you’re researching, restoring, or shopping for an OBS, focus on 1988–1998 model years and use the VIN/year and visible design cues to confirm the generation.
