THE GMC MOTORHOME

Despite their tidy, compact powertrains, neither the Toronado nor the Cadillac Eldorado was especially space-efficient — their flat floors made them more habitable for middle-seat passengers than a typical RWD sedan, but passenger and cargo room were compromised by style-conscious proportions. In a June 1970 Popular Mechanics owners survey, some buyers complained that front-wheel drive wasn’t available in a more practical body style. Bill Mitchell had actually proposed a Toronado wagon early on, but GM didn’t offer FWD sedans or wagons until the eighties and didn’t introduce a FWD light van until the U-body minivans in 1990. In the early seventies, however, the Toronado’s Unitized Power Package found its way into an entirely different sort of utility vehicle, built not by Oldsmobile, but by GMC Truck & Coach Division.

As we mentioned in our first installment, GMC had flirted with the idea of a FWD cargo van back in the fifties with the 1955 L’Universelle. It was an intriguing idea, but probably too costly for the contemporary truck market, which had yet to embrace independent front-suspension, let alone front-wheel drive. The growing popularity of the recreational vehicle (RV) in the late sixties, however, suggested a different avenue. Independent RV builders were snapping up thousands of truck chassis for custom motor homes and GM wanted a piece of that lucrative action.

Front-wheel drive offered some of the same advantages for vans and recreational vehicles that it did for passenger cars: better traction and more room for living or cargo space. Several smaller manufacturers had already gone that route. Since 1963, Clark Equipment Corporation had offered a front-drive RV called the Cortez, which adopted the Toronado powertrain in 1971. The late sixties Tiara and Travoy and the 1972 Revcon were also Toronado-powered, although both were produced in relatively small numbers.

Development of GM’s own FWD motor home began around 1969, initially as a corporate Engineering Staff project. Both GMC and Chevrolet Truck were very interested, but GMC ultimately got the nod because of the motor home’s projected size and gross vehicle weight rating (GVWR). GMC’s general manager, Martin Caserio, saw the FWD project, known internally as TVS-4 (for “Travel Vehicle, Streamlined”), as a utilitarian vehicle that could be offered in many specialized commercial versions, from mobile command centers to airport shuttles.

The TVS-4’s powertrain, front suspension, and front disc brakes were very similar to the second-generation Toronado’s, although some components had to be beefed up to cope with the big RV’s weight. Unlike the Toronado, the TVS-4 had fully independent suspension with optional self-leveling hydro-pneumatic springs and tandem rear wheels — unusual for an RV of this era — located by both leading and trailing arms. The body, which used a combination of aluminum and sheet molded compound fiberglass panels, was remarkably aerodynamic, with sleek, space-age looks courtesy of GMC chief stylist Michael Lathers. GMC even commissioned House & Garden magazine to coordinate the interior color schemes, ensuring that it would be the height of mid-seventies chic.

GMC announced the TVS-4, prosaically dubbed GMC Motorhome, at the TransPro trade show in February 1972, although the Motorhome didn’t actually go into production until early the following year. The Motorhome was offered in two sizes: the Model 230, on a 140-inch (3,556mm) wheelbase, and the stretched Model 260, with a wheelbase of 160 inches (4,064 mm). Both were available either in stripped “Transmode” form for customizers or in a number of fully furnished versions with prices ranging from a base of $13,569 to around $18,000 for a well-equipped Model 260 — expensive but not unreasonable for a Class A motor home in those days.

By the time the Motorhome went on sale, Caserio had departed for a stint at Pontiac, ceding the reins of GMC to Alex Mair. Mair saw the Motorhome less as an affordable family or commercial vehicle and more as a high-end divisional flagship. Since the FWD motor home was always going to be too expensive and too outré to seriously compete with much cheaper RWD truck chassis, it made more business sense to push the Motorhome upmarket. The furnished versions were fairly well-equipped even in standard form and there was a lengthy list of options, ranging from air conditioning with automatic climate control to TV antennas and even a vacuum cleaner.

Initial sales were brisk. GMC sold more than 2,000 in the first year, which was modest by truck standards, but encouraging given the Motorhome’s price tag. Unfortunately, the OPEC oil embargo that fall put a crimp into motor home sales just as it did the passenger car market. The Motorhome was actually fairly thrifty for a big RV, returning as much as 10–11 mpg (21.4–23.5 L/100 km) on the road, but fuel shortages made buyers wary. Slow sales led GMC to two brief production freezes during the 1974 model year. All things considered, the sales decline was modest, but business didn’t really rebound until the 1976 model year.

Although Motorhome production hit a record 3,260 units in 1976, it was still not a big seller by GMC standards and was expensive and labor-intensive to produce. Thanks to its high prices — a top-of-the line Model 260 Kingsley now ran to around $38,000 — we suspect the Motorhome was profitable on a unit basis, but weighed against the number of trucks GMC could produce with the same resources, it probably didn’t make a strong case for itself.

Another factor may have been the imminent demise of the TH425 transmission. Since the biggest engine offered in the 1979 Toronado and Eldorado was slated to be the Oldsmobile 350 (5,737 cc), the E-body cars were about to switch to the lighter TH325 transmission. The Motorhome’s limited production presumably didn’t justify continued production of the older transmission or, for that matter, continuing the Oldsmobile 403 cu. in. (6,598 cc) V-8, which would survive only through the end of the 1979 model year.

GMC general manager Robert Truxell, who had replaced Mair in 1974, announced in November 1977 that the Motorhome would be phased out. Production ended in July 1978; the grand total was fewer than 13,000 units in six model years. GMC eventually sold the rights to the design to California businessman Donald Wheat, who tried unsuccessfully to resurrect the Motorhome in the mid-eighties.

The GMC Motorhome had a prominent role in the 1981 comedy film Stripes, starring Bill Murray, Harold Ramis, Warren Oates, and John Candy, and has also enjoyed several toy incarnations: In 1976, it became the basis of Mattel’s Barbie Star Traveler Motor Home and a vehicle for the Big Jim toyline. The following year, the GMC Motorhome began the first of several runs as a Mattel Hot Wheels car. Surviving Motorhomes have a considerable fan following and various companies continue to offer aftermarket parts and accessories for them; in 1992, Cinnabar Engineering bought a license to manufacture replacement parts, which GMC had recently discontinued. As a promotional effort, one such manufacturer, Dyno Sources of Sequim, Washington, used a modified GMC Motorhome to set a new world speed record for Class A RVs, reaching 102.76 mph (165.38 km/h) on the Bonneville Salt Flats in September 2006. That vehicle, however, was powered by a 454 cu. in. (7,443 cc) Chevrolet V-8, not a Toronado engine.