Q: Greg, my love for older cars takes me back to my teen years when my daily driver was a 1958 Edsel Ranger Sedan which I used to date my future wife who I married in 1975. Since then, my wife and I have grown our antique ownership to six cars, plus our 1977 GMC “Palm Beach” Motorhome.
It’s our motorhome I want to tell you about.
While attending a car show in Columbia, Pa., in 2017, I spotted a 1977 23-foot GMC Motorhome. The owner showed my wife and I the inside and my wife immediately fell in love with it and wanted to get one. I started looking for one within our budget and we found one in Marshall, Michigan.
The owner of the GMC I saw at the car show had given me the phone number of the owner in Michigan, and I asked if he would go along with me to look at it. He agreed and we left on July 4, 2018 and drove out to Michigan.
When we got to Michigan the GMC Motorhome really looked nice. My friend crawled underneath, checked the frame, looked it all over, and said he wouldn’t hesitate buying it.
After agreeing on a price, we had ourselves a 1977 GMC “Palm Beach” Motorhome. The owner said that he had worked at GM right beside where the GMC Motorhomes were manufactured and had always wanted one but didn’t buy this one until he was in his early 80’s.
These GMCs were manufactured at GM truck and coach division from 1973 to 1978 in Pontiac, Michigan. GMC Motorhomes were offered in 23 ft. and 26 ft. models in an aerodynamic low profile design. The big surprise is that these motorhomes were front-wheel-drive and truly unique among the competition. One of the most appealing features of the GMC Motorhome is its low center of gravity which allowed it to ride and handle on the road more like a large car rather than a truck.
It is unclear why GM decided to get into the RV business in the early 1970’s, which was a decade that saw the price of oil skyrocket, but that is exactly what happened.
The new vehicle was known as the TVS-4, Travel Vehicle Streamlined. The GMC Motorhome was a contrast to most motorhomes of the day which were built on heavy-duty truck chassis supplied by a chassis manufacturer.
An RV might have a dual rear axle, but the standard format was two solid axles, leaf springs and a conventional drivetrain layout with an engine up front driving the rear axle via a long driveshaft. The construction was mobile home like and built on top of the chassis, above the driveshaft, which raised the center of gravity. Little consideration was given to aerodynamics and ride comfort.
Originally used in the Oldsmobile Toronado, the GMC Motorhome was equipped with a front-drive transaxle, which GM called a Unified Powerplant Package. The motorhome was comprised of a longitudinally mounted 455-cubic-inch V-8 and a Turbo Hydramatic 425 Transaxle.
Later models made use of the 403 cubic-inch V-8. The Transaxle employed a wide roller chain drive to connect the output engine to the transmission.
The final drive was connected directly to the transmission and power was fed to the front wheels using half-shafts that ran under the front portion of the engine. The engine was fueled with regular gasoline stored in two 25-gallon tanks.
The GMC Motorhome was equipped with front disc brakes and drums on the four rear wheels.
Utilizing the front-wheel-drive layout, the Motorhome didn’t require a long driveshaft or a driven rear axle, which allowed GMC engineers to build the body lower. GM designed the rear suspension as a tandem pair of wheels, mounted on bogies which rode on pins attached to the sides of the low-profile frame. This allowed for a completely flat floor, stretching from the front of the motorhome to the back.
With the exception of the wheel wells, the rear suspension did not intrude into the living space. The rear bogies are suspended using a double-ended convoluted air bag that is pressurized by an automatic leveling system to maintain the designed ride height. The leveling system could also be manually controlled to level the motorhome at a campsite.
The body panels are a combination of fiberglass and aluminum. Fiberglass was used below the waistline frame extrusion and at the ends. Sheet aluminum made up the upper side body and roof panels between the ends. GMC’s are noted for their large, curved glass windows mounted flush to the body, which redefined the RV industry at the time. The GMC’s were available in a variety of colors and striping schemes and the interiors were very plush. Many had luxury features common on upper models of GM brands, such as cruise control, air conditioning and AM/FM 8-track sound systems.
Rear lower compartments provided space for generators and propane tanks. There were no driver or passenger doors at the front of the vehicle. A single door amidships on the right-hand side provided access to the main passenger compartment.
At the back of the vehicle, the entire rear body panel could be taken off by loosening a series of bolts around its edges allowing beds, appliances and other bulky items to be installed or removed.
The wheelbase from the front wheels to the centerline of the rear tandem pairs is 140-inches for the 23-foot models and 160-inches for the 26-foot Models. Gross Vehicle Weight rating for the 23-foot models was 10,500 pounds and 12,500 pounds for the 26-foot models.
A total of 12,921 GMC Motorhomes were produced from model years 1973 to 1978. Since the body was made up of fiberglass and aluminum, and the suspension components were made by a division used in building city buses and heavy duty trucks, it’s not surprising that there are more than 7,000 still on the road.
GM’s Truck & Coach Division discontinued production of the GMC Motorhome on November 11, 1977.
The existing Oldsmobile-sourced driveline was being phased out of production and replaced by smaller displacement engines mounted transversely in front-wheel-drive platforms. GM could not make a convincing business case for converting another engine and transmission to continue production of the motorhome.
Despite the short production run, the GMC Motorhomes still have a huge following internationally. There are several owners clubs, parts suppliers and organized camping events throughout the United States to celebrate these vehicles.
Thanks Greg for letting your readers know about this special front drive GMC Motorhome. My wife and I really enjoy your nostalgia car columns. Steve Stokes, Lebanon, Pa.
A: Steve, I never knew this GMC Motorhome was powered by the Olds Toronado front drive engine and transmission. Thanks so much for all the great information and your kind words.
Greg Zyla is a syndicated auto columnist. He welcomes questions and comments on collector cars, auto nostalgia and motorsports at firstname.lastname@example.org or at 303 Roosevelt St., Sayre, Pa. 18840.