Previously, GM had used the H platform nomenclature to designate the unrelated rear-wheel-drive compact cars.

The LeSabre used a reverse clamshell hood hinged at the front like the Buick Electra, introduced the year before.

The headlights were streamlined with a separated amber turn signal strip wrapping around the lower front fascia.

The rear fascia featured a wider trunk mouth and lower lift over height to ease loading baggage while the front was smoothed with simplified chrome molding and absent bumperettes.

Initially, a 150 hp (110 kW) 3.8 L V6 was the sole engine, mated to a four-speed Hydramatic 4T60 automatic and performance was adequate from this pairing.

The ninth-generation Pontiac Bonneville was unveiled on February 8, 1991, at the 1991 Chicago International Auto Show and launched in July 1991 for the 1992 model year; the interior and exterior of the car were completely redesigned.

Developed over a 4+1⁄2-year period from 1986 to early 1991 under program director Dave Mitchell, styling work took place from 1987 to 1988, with a final design by John Folden being chosen in 1988 and frozen for production that same year.