OBS trucks: Defining the old body style enthusiast term

The term “OBS” is an enthusiast abbreviation for “old body style,” used to categorize classic pickup trucks. While definitions vary among enthusiasts, the term is widely applied to specific generations of Ford and Chevrolet/GMC vehicles.

For Ford, OBS typically refers to 1992–1996 F-150 models and the 1992–1997 “Aero nose” F-250 and F-350 pickups. This classification stems from the period when Ford transitioned from its ninth to tenth-generation platforms, leaving certain heavy-duty models on the older body style for an additional year.

In the Chevrolet and GMC community, OBS refers to the GMT400 C/K platforms produced between 1988 and 1998, though the C3500HD Crew Cab continued on this platform until 2002. Enthusiasts generally exclude the 1973–1987 “squarebody” trucks and the 1999–2009 GMT800 models from the OBS category.