Some cars age and others simply become more expensive to own. A 1987 Buick GNX with barely 30 miles on its odometer has demonstrated just how dramatically collector demand can shift, selling for $427,000 after changing hands for $200,000 only two years earlier, states an online report by Bring A Trailer. The black performance coupe, number 450 of just 547 GNXs built for the model year, has covered only four additional miles since its previous sale, adds the online report.
From $200,000 to $427,000
According to September 2026 report by Bring A Trailer, the GNX previously sold on Bring a Trailer in July 2024 with 26 miles on the odometer. It has since been acquired by the dealer now offering the car in Texas, with the mileage increasing to just 30 miles. The latest transaction more than doubled the car’s previous sale price, highlighting the premium attached to exceptionally preserved examples of one of the most sought-after American performance cars of the 1980s.The car comes with manufacturer literature, memorabilia, copies of its original window sticker, a clean Carfax report and a clean California title, adds the report.
Built to end the Grand National era
The Grand National Experimental, or GNX, was developed as a final celebration of Buick’s Grand National production run. Buick partnered with McLaren Performance Technologies and ASC to turn the already formidable Grand National into a limited-production performance model. Only 547 examples were produced, all in black, making the cars instantly recognizable. The GNX added a collection of visual and mechanical upgrades, including composite wheel-arch flares, heat-extracting fender vents, GNX badging, sport mirrors, dual exhaust outlets and a distinctive three-piece rear spoiler, reads the online report. The car also rides on 16-inch cross-lace wheels and features a limited-slip differential, air conditioning and cruise control.
A turbocharged V6 with serious muscle
If we go by the report, under the hood is a turbocharged 3.8-liter V6 modified by ASC/McLaren. The engine received a Garrett T3 turbocharger, a larger air-to-air intercooler and a lower-restriction exhaust system. Factory output was rated at 276 horsepower and 360 lb-ft of torque. Power reaches the rear wheels through a 200R4 four-speed automatic transmission fitted with an upgraded oil cooler. A GNX-branded aluminum cover distinguishes the limited-slip differential at the rear.The suspension was also reworked and the GNX retained front suspension components from the contemporary Grand National while gaining upgraded rear hardware, including a Panhard rod, torque arm and additional frame crossmember. Power-assisted front disc brakes and rear drums handle stopping duties.
Preserved almost exactly as delivered
Inside, the GNX remains unmistakably rooted in its era. A three-spoke leather-wrapped steering wheel sits ahead of GNX-specific Stewart-Warner instrumentation. The instrument cluster includes a 160-mph speedometer, an 8,000-rpm tachometer and dedicated gauges monitoring turbo boost, oil pressure, coolant temperature and fuel level. The five-digit odometer now reads just 30 miles, making the car less a used performance machine than a remarkably preserved snapshot of Buick’s brief but significant assault on the American performance-car market.
Why the GNX remains collectible
The GNX arrived at the end of an era when turbocharged American cars were beginning to challenge expectations about what a large domestic coupe could do. Its limited production, McLaren-developed mechanical upgrades and distinctive appearance have since made it a cornerstone of 1980s performance-car collecting. For this particular example, the jump from $200,000 to $427,000 in just two years, and with only four additional miles, adds another chapter to that collector story.Image Courtesy: Bring A Trailer
