Pontiac Grand Prix IV (G-body) gallery (1978–1987)

The fourth generation downsized on a revised G-body platform, introducing more efficient V6 and V8 engine options.

All photos 14 I 1 1962–1968 II (G-body) 0 1968–1972 III (A-body) 0 1972–1977 IV (G-body) 0 1978–1987 V (W-body) 0 1988–1996 VI (W-body) 13 1996–2003 VII (W-body) 0 2004–2008

The fourth-generation Pontiac Grand Prix, launched in 1978, embraced General Motors' corporate downsizing initiative to create a significantly lighter and more compact vehicle while retaining its traditional rear-wheel-drive layout on the G-body architecture. Exterior styling transitioned to crisp, aerodynamic lines featuring a formal roof treatment and signature vertical grille themes. Under the hood, the vehicle responded to fuel economy pressures by offering efficient V6 engines alongside traditional small-block V8 powerplants displacing up to 5.0 liters, coupled with manual or automatic transmissions. The interior offered enhanced ergonomics, comfortable seating tiers, and available luxury appointments like power accessories and premium sound systems. Over its extensive run through 1987, the model received numerous updates, including revised front fascias, flush headlights, and special performance-oriented trim packages such as the aerodynamic Grand Prix 2+2 homologation special. Main sales territories remained concentrated in the United States and Canada.