A nearly century-old American roadster is drawing attention on Bring a Trailer as a 1928 Pontiac Series 6-28 Sport Roadster heads to auction. Representing Pontiac’s early push into affordable performance, the open-top classic combines pre-war engineering with distinctive styling details that defined the late 1920s.
This particular example was refurbished under previous ownership before being acquired by the selling dealer in 2025. It is now offered in Bremerton, Washington, finished in gray with yellow bodyside stripes and black fenders — a color combination that highlights the long hood, upright grille, and sweeping fenders typical of the era.
Pontiac introduced the Series 6-28 as part of its effort to deliver more power than many competing cars of the time. Under the hood sits a 186.5 cubic-inch L-head inline-six, factory rated at 40 horsepower. The engine breathes through a single Stromberg updraft carburetor and sends power to the rear wheels through a three-speed manual transmission.
While those numbers may sound modest today, they represented strong performance for a car of this class in 1928 and helped Pontiac establish its reputation during the early years of General Motors’ expanding brand lineup.
The roadster body itself was built by W.F. Stewart of Flint, Michigan, and features a number of period-correct details including cowl lamps, a passenger-side spotlight, running boards, and a radiator mascot mounted up front. A black soft top, single rear taillight, and classic rumble seat further reinforce the car’s late-1920s touring character.
Out back, the rumble seat is trimmed in black upholstery and includes a collapsible luggage rack mounted in the footwell, a practical feature for road trips during the era.
Inside the cabin, the bench seat is trimmed in brown vinyl with matching door panels and contrasting dark brown storage pockets. A black textured rubber mat covers the floor, maintaining a simple, utilitarian interior typical of the period.
The wood-rimmed steering wheel frames a painted steel dashboard with a central instrument cluster featuring an 80-mph barrel speedometer alongside gauges for fuel level, oil pressure, and amperage. The five-digit odometer shows 75,000 miles, though the total mileage is unknown.
The Pontiac rides on 20-inch wood-spoke wheels fitted with BFGoodrich Silvertown bias-ply tires measuring 4.75/5.00–20. A spare rim and tire are mounted at the rear. Suspension consists of solid axles supported by semi-elliptical leaf springs, while braking is handled by four-wheel mechanical drum brakes.
With its 110-inch wheelbase, classic rumble seat configuration, and period mechanicals, the car represents a snapshot of American motoring just before the Great Depression reshaped the automotive industry.
The roadster is offered with side curtains and transferable New York registration, which serves as the ownership document in that state. The registration is currently expired.
As pre-war automobiles continue to find dedicated enthusiasts, examples like this 1928 Pontiac Series 6-28 Sport Roadster offer a tangible link to the earliest decades of performance-oriented American cars — long before horsepower wars and muscle cars defined the landscape.
Eve Nowell