Even longtime Chevrolet truck fans may be unclear on the precise definition of lingo such as square body and OBS Chevy. This is because there is some variation in the meaning of this slang. But don’t fear, I did a deep dive on all the things OBS Chevy can stand for so you don’t have to! Read on to find out everything about OBS Chevy pickups.

What is an OBS Chevy?

OBS Chevy usually refers to the generation of Chevrolet/GMC pickup truck built from 1988 through 1998. Personally, I always believed the acronym stood for “old body style.” Other automotive journalists write that it stands for “original body style.” The difference may be regional, and anyhow it means the same thing.

While fans of Dodge and Ford trucks refer to an undefined older generations of their pickups as “old body style” or OBS, GM fans almost all refer to the first chassis that wore the Sierra nameplate as the OBS (1988-99). This may be why some GMC pickup owners say OBS stands for “original body style.”

What year Chevy is OBS?

Chevrolet replaced the “Rounded Line” pickup (often called the square body Chevy) with its new C/K truck in 1988. It continued to build this generation–also called the OBS Chevy–until 1998.

The OBS Chevy features more rounded lines than its predecessor because it was the first aerodynamic influenced truck on the market. General Motors’ had an internal code for the 1988 through 1998 generation of its Chevrolet C/K and GMC Sierra. The automaker called this chassis the GMT 400. OBS Chevy is obviously a slang term that fans of the truck have adopted.

Referring to any generation of truck as the “old body style” obviously becomes problematic as successive new generations come out. Who knows, maybe in a few decades someone will call a 2023 Chevrolet Silverado an OBS Chevy. But for now, the consensus is that an OBS Chevy is the GMT400.

With independent front suspension and fuel injection, these OBS Chevy pickup trucks are prized for modern driving characteristics paired with vintage good looks. See how an OBS Chevy stacks up to a modern Silverado for yourself in the video below:

When did Chevy stop making OBS?

The last generation of the Chevrolet C/K trucks, often called the Chevy OBS, ran from 1988 through 1998. In 1999, Chevrolet introduced the first generation of the Silverado (which confusingly coincided with the second generation of the GMC Sierra)–replacing the Chevy OBS.

The 1999 GMC Sierra/Chevrolet Silverado featured much more rounded lines than its predecessor. Its slanted headlights make it instantly recognizable. This new generation is often referred to as the GMT800.

What engines were in the OBS Chevys?

You could order an OBS Chevy pickup truck with a range of engines. The base model came with a 4.3-liter V6. Your gas V8 options ranged from 5.0-liter all the way up to 7.4-liters. General Motors also offered a naturally-aspirated and a turbocharged diesel V8.

See one die-hard fan make a case for why you should go buy a used OBS Chevy Silverado pickup truck today in the video below:

Are OBS Chevys reliable?

If you are used to working on modern cars, you may prefer an OBS Chevy to an earlier generation. This is because it was the first GM truck generation to exclusively use modern technologies such as fuel injection and independent suspension even on its 4×4 trucks. It even did away with locking hubs so you could shift into 4×4 from the cab.

If you are used to carburetors and solid frond axles, the OBS Chevy might be a pain to work on. Every old vehicle will have some mechanical issues. And it’s important to remember that a 1988 OBS Chevy is over thirty years old. But they have a reputation for being reliable.

Common complaints against the OBS Chevy include poor quality interior plastics, paint that fades in the sun, small stock brake rotors, and lots of rust in certain climates–according to MotorTrend.

Next, read everything you need to know about square body Chevy trucks or learn more about OBS Chevy pickups in the video below: