The G-body designation was originally used for the 1969–1972 Pontiac Grand Prix and 1970–1972 Chevrolet Monte Carlo personal luxury cars, which rode on longer wheelbases than A-body coupes.

These special coupes included the Monte Carlo, Grand Prix, Oldsmobile Cutlass Supreme, and Buick Regal.

For the 1982 model year, GM introduced a new front-wheel drive A platform for its mid-size car lines.

NASCAR regulations continued to stipulate production body parts until 2003 (namely, the hood, roof, and deck lid), but since most of the vehicles that bodies were derived from during this period had a transverse front-wheel drive layout (many even lacking a V8 as an option), the drivetrain and all running gear were either custom-built or sourced from other (usually, older) models.

The 1987 GNX was made in conjunction with ASC/McLaren and 547 were made, which included a unique suspension system, fender flares, Stewart-Warner gauges, larger Garrett turbocharger and intercooler, and a net power of 276 hp (206 kW), above the 245 hp (183 kW) of the regular Grand National.