Chevrolet Corphibian

History

Richard E. Hulten and Roger D. Holm were engineers at General Motors. The Lane Motor Museum and a 2025 Jalopnik article call them Pontiac engineers, while Silodrome and The Drive call them Chevrolet engineers ^[1][2][5][6]. Working in their spare time, they set up a company, Hulten-Holm Co., rented a garage in Pontiac, Michigan, and bought a new Corvair 95 Loadside pickup from a Chevrolet dealership ^[2][6]. They hoped Chevrolet would buy the design, perhaps as a special-order option for the Loadside ^[1][2].

Jalopnik describes 1961 footage in which the pair drive the truck straight into a Michigan lake and then run it from the controls in the bed ^[5]. Silodrome says the testing was done mostly afloat and covered stability, speed, carrying capacity and driving in and out of the water ^[2]. Jalopnik reported in 2015 that GM studied the vehicle for two years before deciding against production ^[4]. Later accounts give the reasons as cost and the small market for amphibious vehicles, and Jalopnik adds that Amphicar sales had not taken off ^[2][4][5]. The Lane Motor Museum says the Corphibian was not an official Chevrolet project ^[1]. The Mecum auction catalog, whose descriptions Mecum says come from the seller, tells the story differently: it says GM commissioned the vehicle and that Chevrolet Engineering built it with Hulten-Holm ^[3].

Design and how it works

The conversion stretched the rear of the truck by about 2 ft (0.6 m) to hold a hydraulic reservoir and motors ^[2][4]. A pump on the Corvair's rear-mounted, air-cooled flat-six engine supplied the hydraulic pressure, and belts carried power from the hydraulic motors to two propellers behind the rear wheels ^[1][4]. Below the body they fitted a molded fiberglass pan to keep the water out ^[2][6]. Silodrome, Jalopnik and The Drive describe two electrically operated rudders, while the Mecum listing mentions a wooden rudder ^[2][3][4][6].

Most of the boat controls were in the pickup bed, and the throttle could be worked from the bed or the cab ^[1][5]. According to Jalopnik, the doors could be opened while the truck was afloat, which let passengers move between the cab and the bed on the water ^[5]. On land it kept the Corvair drivetrain, which the museum lists as an 84 bhp flat six with a two-speed automatic transmission, and the museum gives a top speed of 90 mph (145 km/h) ^[1]. No measured water speed was found in the sources consulted; Silodrome gives no figure beyond a few knots on calm water ^[2].

Later history

Accounts of the next three decades differ. Jalopnik reported in 2015 that Hulten kept the truck in storage for about 30 years, sold it to Wally Wheeler in 1993, and that it later changed hands again ^[4]. Silodrome and The Drive say instead that it passed into private hands after the project ended and was found by Wheeler, an amphibious vehicle collector, in 1993 (Silodrome) or the early 1990s (The Drive) ^[2][6]. It was later restored to working order ^[2][6]. When Mecum sold it at its Kissimmee, Florida, auction on January 23, 2016, the lot included a signed statement from Hulten and Holm dated July 30, 1995 ^[3]. Mecum lists it as sold for $77,000 with 157 miles (253 km) showing ^[3]. The truck is now on public display at the Lane Motor Museum in Nashville, Tennessee, in red and white, with its original air-cooled engine, automatic transmission and two propellers ^[1][5].

Related entries

• Amphicar 770Amphibious cars · 1961 to 1968
• Hobbycar B612Amphibious cars · 1992 to 1996
• Ravaillier Canot-Voiture (Waterland I)Amphibious cars · 1907
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