Story Of A Classic: The GMC Motorhome
By Bill Bryant, F65627
Produced by General Motors from 1973
through 1978, the innovative GMC Motorhome gained a following that is
still as strong --if not stronger -- today.
Following World War II and a lapse of auto
production of nearly four years, former GIs and the general public longed
for new cars. Once the pent-up postwar demand was satisfied, auto
companies started offering innovative, attractive new designs in an effort
to capture a greater market share. At auto shows and Motoramas we saw
Thunderbirds and Edsels, Chrysler 300s, Corvettes, GTOs, and Eldorados.
New V-8 engines were everywhere; small blocks, big blocks, Hemis;
horsepower and cubic inches ruled. New styles were longer, lower, wider,
with chrome everywhere and tail fins that soared.
Then came the energy crunch in October
1973, and it all changed. The automotive talk turned to cost and
availability of fuel, more efficient cars with new four-cylinder and V-6
engines, and downsizing. Cars became smaller, lighter, less powerful, and
with increased fuel economy standards mandated by the federal government.
Automobile companies are always searching
for ways to gain more sales, to build a greater market share, and to keep
their assembly lines flowing. New ideas are constantly evaluated, but few
see the light of day. Occasionally, however, a niche is found and a new
market is developed.
Truck chassis were successfully marketed to
the RV industry in the 1970s by the Big Three. In 1971 Dodge sold 28,000
chassis to 50 different coach builders. Each RV manufacturer was building
its version of what it thought a motorhome should be. There were lots of
choices for the motorhome buyer, nearly all of them on a truck chassis.
What if someone offered an attractive, advanced design on a custom
chassis, unique and specifically made for just that purpose?
One of those niches GM was looking at in
1969-1970 involved ideas for a multipurpose vehicle -- a vehicle that could
be adapted for use not only as a motorhome, but as an ambulance, a small
transit bus, an airport shuttle, a mobile medical clinic, or a display or
service van. Evaluations began at the GM Tech Center in Warren, Michigan.
Competing motorhome specifications were scrutinized, and floor plans were
evaluated. Initially, it was decided to go with 20-foot and 24-foot
motorhome designs.
Relying heavily on interior designs by GM's
Frigidaire Division, drawings of the numerous floor plans under evaluation
lined the Tech Center's walls. A full-scale plywood (fiberboard) seating
buck was built in the Tech Center's basement to evaluate the different
interior designs. Seating bucks are used to define a vehicle's
requirements for both internal and external packaging. Styling must not
violate these requirements if their designs are to remain true for the
final production version.
The first chassis built to demonstrate the
unique vehicle design was assembled with the now familiar tandem-rear
wheel assembly incorporating leading-trailing cast nodular iron arms at
the rear, supported with a hydro-air spring from the Saginaw Division of
GM. The power steering pump was used for hydraulic pressure for this
suspension system. The engine and drivetrain used the Oldsmobile Toronado
front-wheel-drive unit with its 455-cubic-inch engine, 425 Hydra-Matic
transmission, and 3.07:1 differential gear ratio from the Toronado
trailer-towing option.
The design of this "development mule"
allowed for a low-profile chassis with its attendant handling and ride
improvements. The front section of the frame made use of the Toronado
design and bolted up to the center C-channel side rails. The rear frame
extension was unique to the motorhome and was "kicked up" to allow for an
adequate departure angle. A modified van body built by the Union City Body
Company, of Union City, Indiana, was mounted on the frame. The chassis had
been designed with only 4 inches of ground clearance.
Called the "pie wagon" or "chicken coop" by
those working on the project, this development mule was outfitted with
windows and bus seats, and sand bags were strategically placed inside to
represent the weight of an equipped motorhome. Since spy photographers
often took pictures of test vehicles driving around the GM Proving
Grounds, full fender skirts covered the wheels to hide the vehicle's
unique suspension.
The major purpose of this vehicle was to
demonstrate to GM management its superior handling and ride in comparison
to the truck chassis normally used for motorhomes. It is reported that GM
management was favorably impressed and approved further development of the
project.
Initially, Chevrolet wanted the motorhome
project, but the GM corporate guidelines defined vehicles below 10,500
pounds gross vehicle weight rating (GVWR) as Chevrolet responsibilities
and vehicles above that weight as GMC responsibilities. The project,
therefore, went to GMC. This decision, however, did not stop the
interdivisional rivalry, which continued throughout the motorhome's
production years. Chevrolet was a major supplier of truck chassis for the
RV industry and considered the GMC Motorhome another competitor. Chevrolet
management made sure that the motorhome carried all of its cost burdens
and received no special corporate advantages.
Early in these developmental stages, GMC
Engineering was defining just what this multipurpose vehicle should be.
The GMC styling idea was along the lines of the Sportscoach motorhome of
the period, with styled front and rear fiberglass caps, but with straight
sidewalls. This type of design allowed for a reasonably attractive
appearance, though ordinary, while minimizing tooling and manufacturing
costs.
The GM Design Center had been at work for
about two years at this point on various multipurpose vehicle designs. Not
surprisingly, those designs looked much different from what GMC had in
mind. There were three-wheeled designs that followed the arc of the sun
while parked; panels that extended to add more living space; and scale
models of attractive and futuristic designs, as well as numerous sketches
and drawings that were ... well ... far out!
The use of the Oldsmobile Toronado
front-wheel-drive unit should not have been a surprise. Four other
motorhome manufacturers were utilizing that same system during this time
period: Revcon, Cortez, Travoy, and Tiara. The Revcon was the most
successful of the group. Cortez had evolved from the Clark. Travoy was a
Riverside, California, company. And the Tiara evolved from the Ultra Van,
which had originally used the Corvair engine.
The individuals responsible for the
development of the GMC Motorhome were members of a group of bright young
professionals. Martin J. Caserio, General Motors vice president and GMC
Truck and Coach general manager, envisioned a "Chevrolet" of motorhomes -- that is, reasonably priced with a view toward large-volume sales. Caserio's replacement in 1973, Alex C. Mair, wanted a vehicle more like
the "Cadillac" of motorhomes, more upscale than the early models. A
bright, young, enthusiastic engineer, Kurt Stubenvoll, was in charge of
product development for the motorhome. Ralph Merkle headed up chassis
development and was responsible for everything from "the frame to the
pavement." Known as "the idea man," Merkle had a number of patents to
prove it. John Locklin came to GM with an aeronautical degree and had
responsibility for the motorhome body engineering (he brought new assembly
methods and ideas to the auto industry). Michael Lathers from the Design
Center was in charge of the motorhome styling (it was to become obvious to
all the fine job he did). Many other talented engineers contributed to
what was to become a classic as well.
On February 7, 1972, GM made official what
had been rumored in the industry for some time. The national press
reported that GM was to "play a role in the motorhome market." By this
time, the motorhome's lengths had been identified as 23 and 26 feet. The
increase in length was the result of additional interior content that
designers and salespeople felt was necessary for a well-equipped motorhome.
GM Sales had identified the need for the 23-foot motorhome as a price
leader. Prices were reported to be between $12,000 and $16,000. Major
motorhome competitors claimed they were not worried; still, their stock
prices fell several points the next day. Smaller motorhome companies
indicated immediate concern about the erosion of their market share with
giant GM entering this field.
About this time the new vehicle was known
as the TVS-4 (Travel Vehicle Streamlined model 4). Part of the reason this
vehicle is so different from other motorhomes of the era is that it was
not conceived as just a "camper," but as a vehicle for comfortable travel
as well. Slogans used later in GMC Motorhome advertisements demonstrated
this; for example: "It doesn't ride like a truck, it doesn't look like a
box." "Our goal was to make getting there as much fun as being there."
"It's as easy to live with on the road as it is standing still." "The show
place that goes places." All of these slogans placed great emphasis on the
traveling aspects of motorhoming and not just how a motorhome functioned
while parked at the campsite.
Produced by General Motors from 1973
through 1978, the innovative GMC Motorhome gained a following that is
still as strong -- if not stronger -- today. This three-part series explores
the fascinating history of a motorhome still considered by many to have
been far ahead of its time. Last month, Part 1, discussed how the GMC
Motorhome was conceptualized and developed. This month's installment
covers completion of the design, building of prototypes, and the beginning
of testing.
Design of the GMC Motorhome continued to
evolve in the two main areas of styling and chassis, with the Design
Center concentrating on the external and interior designs. At one time,
there were 12 designers working with sketches and 1/8-scale (called
A-scale) clay models. Three or four of these clay models were made, each
with distinct design characteristics, and each refining its shape closer
to the final form.
Since only one side of a model could be
viewed at a time, the first scale models were sculpted with two different
designs, one on each side. Thus, a single clay model could be used to
evaluate two different designs at the same time. The final A-scale model,
however, would be viewed as a completed single design.
Once these models were completed,
evaluated, and approved, full-sized drawings were made using 1/4-inch tape
to outline the front, rear, and side designs. These drawings would guide
the designers in the next stage: a full-size clay model.
An important part in developing the shape
of this motorhome was to determine just how efficient it would be moving
through the air. While the design looked "clean," tests would determine
whether in fact it was. GM used various methods to determine this in its
vehicle designs. One method was to put ink spots on a model and place the
model in a wind tunnel to watch the directional flow of the ink. In
another test method, small ribbons were fastened to the surface of a test
vehicle and a camera car was driven alongside the vehicle to photograph
the directional flow of the ribbons. While either of these methods may
have been used, what is known is that a 1/16-scale model was built for the
purpose of determining the coefficient of drag, known as CD. A mahogany
block was modeled to the designed shape, and a fiberglass model was then
made from this master. Holes were drilled about one inch apart over the
fiberglass body, and flush-mounted, hollow tubes were installed and
connected to pressure-measurement devices. Time was purchased at the
Guggenheim wind tunnel facility in California, and the test was performed.
Was the shape clean? You bet! The CD was .310, better than that era's
Corvette, which was .312.
A great deal of clay is required for a
26-foot motorhome, probably the largest clay model GM ever made. The clay
had to be heated in an oven to 150 degrees Fahrenheit to soften it so that
it could be applied to the substrate, which in this case was Styrofoam. It
was then scraped and shaped by the modelers. The clay buildup continued
until the dimensions of the design were achieved. This work was done in
the basement of the Tech Center in an area without a well-controlled
environment, and without air-conditioning. Each morning the room had to be
brought up to temperature so that the clay could be worked. Once the shape
was completed, the clay surface was "polished" with a sponge and cold
water. This full-size clay model, now identified as RV-26, was finished
with a silver-blue film of Di-Noc, replicating the painted surface of a
vehicle.
Once the full-size clay model was
completed, plaster casts were made of it. Dimensional drawings of these
casts were made for tooling and for building the early fiberglass parts
for the first prototype bodies. The full-sized clay model existed for only
about a month, after which it began to sag. Since it was no longer needed,
it was destroyed.
Pictures of the scale models, the sketches
and drawings, and finally the full-size clay model are most interesting.
The evolution from the earliest designs, with pronounced fender flares,
wraparound rear windows and taillights, and other eye-pleasing shapes,
drifted toward a still pleasing but more "manufacturable at reasonable
cost" design in the end.
Changes made to the clay model after being
"finalized" were the incorporation of the parking lights below the
headlights within the headlight bezel area and the use of four Suburban
(production) taillights. The quad taillight idea, however, was quickly
discarded as being too cluttered. Designer Mike Lathers proposed a couple
of other features that didn't make the cut; these included a crown (curve)
in the rear window glass, which would have minimized reflections caused by
a large window surface. Another of Mike's novel ideas was to accent the
rear suspension, instead of hiding it (a polished, plated, and painted
suspension assembly, much like Harley-Davidson does with a motorcycle).
The view of a "flashy" suspension in action would have been an impressive
sight. Even though some of the suggested features didn't materialize, I
have yet to meet a person who doesn't think that the GMC Motorhome is
arguably the nicest design to ever come down the RV pike. When I look at
the earliest renderings, I usually have a big smile on my face, thinking
of what might have been.
In parallel with the exterior work at the
Tech Center, six designers were developing the interiors. The plywood buck
mentioned earlier helped to define space and floor plan requirements. An
important consideration was the loading of the vehicle, distributing the
weight as evenly as possible. Considerable effort was made in evaluating
competing interior features. At one point, it also was suggested that the
Frigidaire Division might build RV appliances, stoves, and refrigerators.
But with a limited market and very competitive pricing, Frigidaire decided
there were better business arenas available.
House and Garden magazine was used
as a consultant for the interior décor and exterior colors. This
publication was the authority on the colors of that era. Ed Cole, GM
president, suggested that bright colors should be used. One story -- confirmed by several people
-- reported that during one meeting in which
colors were discussed, Ed Cole pointed to the tie of chief engineer Wally
Edwards and said, "One of the colors should be like Wally's tie." The tie
was adorned with orange stripes; an orange color (bittersweet) was offered
in 1973-74. Wally still has that tie.
The chassis design was continuing as well.
The engine and drivetrain layout was progressing rapidly, since it
required only minor changes to the existing Oldsmobile Toronado design.
Ralph Merkle's original 24-foot design had been stretched to 26 feet in
order to make room for the interior furniture and appliances. This
displeased Ralph, who had envisioned using many existing GM passenger
vehicle components to keep the motorhome price affordable. Now additional
length and weight were going to compromise the use of these parts, as well
as the front-wheel traction.
Ralph Merkle related a story about the
frame design. When the design was nearly completed, Ralph asked John
Locklin for the final body design details, because frame and body designs
had to be coordinated. However, the body design was not yet finalized.
Since lead times for the frame subcontractors were critical, Ralph was
forced to make his best guess. His guess was off by about 2 inches. That
is why the rear frame cross member sticks out about 2 inches beyond the
body. The frame was made of 1/8-inch-thick steel by Midland.
Ralph and John enjoyed some good-natured ribbing during this process.
Ralph kidded John that his frame was holding up John's body, and John
would respond by saying it was his body holding up Ralph's frame. They
were probably both right.
The rear tandem-axle hydro-air suspension
designed by GM's Saginaw Division had been the key design element for this
vehicle. It allowed for the low floor as well as a measured improvement in
ride and handling. Another feature was less intrusion into the living area
than dual wheels would have caused. Tooling costs for the hydro-air design
had come in much higher than anticipated, however. A less costly design
was requested as a backup, and work began on a replacement.
A full air spring was designed. A Goodyear
model using a long cylindrical (air) spring, one piston, and one bag
convolution had been found to have interference problems. A new full air
spring design was started using the rolling lobe principle with two
tapered pistons and a floating air spring between them. The tapered
pistons kept the spring centered, and as the rubber spring rolled up and
down the piston surface, the spring rate was changed. The first prototype
spring was delivered by Firestone in March 1971 and became the production
air spring with only a minor modification (slightly larger in diameter and
slightly shorter in length).
In the Experimental Engineering area, five
pre-test chassis were being built. The pre-test bodies would later be
installed on four of them. The fifth chassis would be used for pictures
and display. The completed units would be used for various purposes -- some
for testing, some for pictures and shows. We will hear more about these
later.
John Locklin, the body engineer, was
spending most of his time at G.L. Bowen & Co., the job shop that was
supplying the draftsmen charged with documenting the motorhome body.
Measurements of the plaster casts made from the full-size clay model were
translated into drawings to be used to make the dies, body structure, and
skin. John's background as an aeronautical engineer was showing up in many
of the design features -- for example, the light weight of the aluminum and
fiberglass body skin, the all-aluminum body framing, and the bonding of
body panels with adhesives instead of rivets and screws. Another important
design feature was the use of flat aluminum panels for body surfaces above
the belt molding, including the roof. No body stampings were required,
thus minimizing tooling and fabrication costs. John also had insisted on a
flat driver's compartment floor. In driving a competitor's motorhome, he
found that having to squeeze between the driver's seat and the engine
cover was uncomfortable and, in his mind, unnecessary.
GMC Engineering was attempting to build the
side window frames out of plastic. While windows with sharp corners were
in vogue at the time, Mike Lathers felt this design resulted in stresses
at the corners that could eventually cause cracks in the body skin. The
rounded corner design reduced these stresses and provided a less dated
look. The plastic frames couldn't be made to work, however, and a
multi-piece aluminum frame was put in production. A few years ago I asked
a GMC engineer why GMC changed to Hehr windows in 1976, and he said the
anodizing on the earlier windows didn't match. He said they couldn't build
them, couldn't seal them, and couldn't service them. GMC initially planned
for the window frames to be "bright." At one of the design reviews, they
hadn't yet gotten around to plating the frames and they were painted
black. Those reviewing the design liked the black frames better, and that
settled that.
The large body dies required for the SMC
(sheet molded compound) fiberglass panels were in place at the vendor,
Engineered Molding Systems of Lancaster, Ohio. Lumps of SMC "dough" were
strategically placed in the molds, and with heat and pressure, it took 12
minutes to process each panel. This cycle time was reduced somewhat as
experience was gained with the curing process.
At GMC, the first hardware that we would
recognize as a GMC Motorhome was being assembled. The chassis with the
Toronado front-wheel-drive assembly was pretty well defined. The rear
suspension was still the tandem-axle hydro-air suspension, and many
components were still passenger car parts, such as the five-bolt wheels
and hubs. In viewing the body hardware, things were a little different
from how they had appeared in the clay model. The front end was nearly the
same, but the sides had become vertical and straight. This particular
vehicle was to become known as "straight sides," not usually uttered in a
complimentary tone. It turned out that GMC engineers thought the upper
storage cabinets should be able to hold a 12-inch plate, and the tumble
home (body side curve) design created by Mike Lathers didn't allow for
that. At the rear of the body, the large removable back panel had not yet
been implemented.
When Mike Lathers got a look at straight
sides, it is reported that he "went straight up in the air." The design
looked a lot like any other motorhome of the era. In selling the design to
GM management, the point had been made that anybody could make an
ordinary-looking motorhome; what GM needed was "style" to sell. And style
is what they got. Mike lobbied for and won the argument to have his design
reinstated. That was the last of "straight sides."
GMC had decided to outsource the interior
up-fitting. Bids were received from four manufacturers: Open Road,
Sportscoach, Muntz Corp., and PRF Industries. Muntz Corp. had returned the
most attractive bid, but they were located in California. GMC officials
desired someone closer to Pontiac, Michigan. Although its bid was not the
lowest, PRF Industries received the nod, since its location was to be 22
miles from the Pontiac plant, and further negotiations brought its bid
close to GMC's price point.
PRF Industries was owned by Peter R. Fink,
the builder of Travco and Sightseer motorhomes. A new PRF division was
formed to build the GMC interiors, Gemini Corp., located in Mount Clemens,
Michigan. Rumor has it that Peter Fink named the new corporation "Gemini"
because it was "GM & I." Rumor also has it that his zodiac sign may have
been Gemini; take your pick on which (or both) you want to believe.
The Gemini facility designed and built all
of the furniture; assembled all of the modules; applied the Texolite
laminate; and installed everything, bringing it in through the motorhome
rear access opening. A number of start-up concerns had to be resolved.
Between the motorhome body manufacturing tolerances and the interior
module tolerances, which were affected by temperature and humidity,
changes had to be implemented to make things fit. Every wooden part had to
have a drawing and a GM part number. The complexity of 15 different floor
plans and the many available options contributed to a complicated interior
assembly process as well. Approvals from the many individual states as
well as from the federal government had to be submitted and granted also.
Gemini had a target of completing the interiors of 32 coaches per day; the
best they achieved was closer to 20 per day.
With the prototypes now being assembled,
and their purposes defined, their activities would begin. The first public
showing would be at Transpo 72, the U.S. International Transportation
Exposition near Washington, D.C. (Dulles), from May 27 through June 4,
1972. Many GM cars and trucks were on display there as well as a
tan-colored 26-foot motorhome. The exterior was rather plain, with no
stripes or trim. In a brochure it was described as "An experimental
prototype of GMC Truck & Coach Division's complete motorhome, to be
marketed in early 1973." The display was still labeled as a "Multi Purpose
Vehicle," although this term would not be used again, as all efforts were
now focused on developing and producing a motorhome.
Other motorhome prototypes were undergoing
testing. A 23-foot motorhome model named "Cape Cod" was at bench test.
Programmed testing with replicated Belgian blocks (cobblestones) cycled
the suspension with hydraulic rams. Door latches were slammed, windshield
wipers were cycled, brake pedals were pumped, all through a determined
number of test cycles. Coaches were also run for what seemed like endless
hours at the Milford, Michigan, GM Proving Grounds. Hot-weather testing
was carried out on the "Baker Grade," an 18-mile-long hill in the deserts
of Southern California. This hot-weather testing resulted in an additional
fan blade being added; use of the seven-bladed fan was now dictated.
Modified passenger vehicle test criteria
were used, consisting of proving grounds roads for 25,000 miles (regular
durability) and 5,000 miles of Belgian blocks (accelerated durability).
During the "figure 8" road testing, an early failure was the five-bolt Toronado passenger car wheels. They were replaced with eight-bolt one-ton
truck wheels. This also required replacing the hubs to match the
eight-bolt pattern. Another failure was a cracked frame near the front
cross member. The addition of a diagonal brace fixed this problem. The
front suspension's lower A-frame and lower ball joint were other areas
that required upgrades to the passenger vehicle parts.
Crash tests were performed at 30 to 35 mph
as well. From Pennsylvania dealers, GM had purchased new Buicks that had
been in a flood. The side crash test aimed the Buick at the motorhome's
large side window area. The Buick's bumper penetrated the sidewall and
came to rest above the floor. New aluminum vertical reinforcements were
added, and this problem was fixed. The rear crash test resulted in damage
to the frame kick-up area and spare tire carrier. Changes in this area
fixed this as well.
A rollover test was also performed. The
proving grounds had a rollover ramp designed for just that purpose. This
worked well for passenger-type vehicles, but long wheelbase vehicles
usually had to be assisted. A forklift raised one side of the frame to tip
it over, 1-1/2 to 2 turns. The damage was reported to be not all that
serious: a toilet had come loose along with a few other interior pieces,
and the body was distorted to one side.
Plans for the manufacture of the motorhome
were moving along rapidly. Plant No. 3 in Pontiac, Michigan, had been
outfitted with equipment and tooling. This was one of GM's older plants,
and it had a split-level floor plan. At the lower level, the chassis frame
was collecting various subassemblies as it proceeded down the line: front
and rear suspension, tanks, air lines, electrical wiring, and, finally,
the engine and drivetrain.
The upper level of the plant was used for
body assembly. Individual aluminum pieces of the frame were placed in
manufacturing jigs, which assembled and aligned them; the pieces were then
welded together as a unit. Three unique jigs were used: right side, left
side, and the roof assembly. Next, these panels were assembled and welded
together as the body cage. Separately, each of the body panels was very
flexible. When welded together, they became a strong yet lightweight unit.
Aluminum and fiberglass exterior body panels were fastened to this frame
with a 3M adhesive. John Locklin had wanted to use an adhesive made by a
small company called REM, but GMC wanted a larger, well-known supplier
instead. This assembled body was then cleaned, prepped, and painted.
When completed, the body was lowered to the
main floor, where it was mated with the assembled chassis.
The first few motorhomes moved slowly down
the assembly line during the fourth quarter of 1972, and by the second
week of November the first two dozen had been built. The first 100 were
finished before the end of January 1973, and more than 1,750 orders were
received by mid-February. In March 1973, Alex Mair, general manager of GMC
Truck & Coach, reported, "The initial response has surpassed even our most
optimistic expectations." It was reported in June of that year that back
orders totaled 3,000 units, and the rate of motorhome production was about
20 units per day.
As might be expected, there were some
startup problems. A new group-assembly concept was developed, with a
six-member team responsible for body and trim upfitting and a three-member
team for assembling and upfitting the chassis. This team concept lasted a
month or two, but then production reverted to the standard Detroit auto
assembly method of individual job responsibilities.
With the complexities of a new facility, a
new workforce, the assembly of a totally new vehicle, plus all of the
living requirements (including the proverbial kitchen sink), GMC Motorhome
production was indeed an ambitious and complex undertaking. Alex Mair was
holding "design school" with the engineers each morning at 7:30 to address
any concerns or problems and to review progress. He often would walk
through the plant to discuss the day's activities with line employees.
By June 1973 GMC had 64 dealers signed up
to sell and service GMC Motorhomes. Company officials had hoped to have
200 dealers by the end of 1973 but decided not to sign up any more until
adequate supplies were available. GMC Motorhome dealerships were separate,
stand-alone entities, and GMC truck dealerships didn't automatically
become GMC Motorhome dealers. The cost of a GMC Motorhome dealership
franchise was reported to have been $250,000.
The 1973 GMC Motorhome was available with a
choice of four models, six exterior colors, 15 floor plans, and two body
lengths. And then there was the long list of available options. The
"Detroit" mentality of something for everyone had arrived full force in
the RV industry. The first series of motorhomes were named for national
parks -- Canyonlands, Glacier, Painted Desert, and Sequoia -- and the
26-foot and 23-foot coaches used the same model names. Three of the
exterior colors were standard -- white, camel, and pineapple yellow -- and
three others -- bittersweet, sky blue, and parrot green -- were optional for
an additional $34. A horizontal accent color stripe wrapped around the
front of the body; continuing the stripe down the sides of the coach was
an $86 option.
The total of 15 floor plans was split
between the two body lengths, 11 for the 26-foot coach and four for the
23-footer. Any floor plan was available in any of the four models. The
model names defined the interior décor, colors, and upholstery patterns
and not the floor plan.
Manufacturer's suggested retail base price
was $14,569.06 for the 26-foot motorhome and $13,569.06 for the 23-foot
motorhome. Almost everything was available as an option. Possibilities
included auto air, $482; AM-FM radio, $217; chrome bumpers, $75; wheel
covers (7), $52.50; suspension power-leveler, $85; built-in vacuum
cleaner, $210; roof air, $525; auxiliary 6-kw generator, $1,675;
factory-delivery drive-away prep, $32; or customer drive-away prep, $105.
A number of RV shows and demonstrations
were used around the country to exhibit the features of the new GMC
Motorhome. GMC even displayed the motorhome at a truck show in Frankfurt,
Germany -- the Germans loved it! During one of the most impressive
demonstrations, a GMC Motorhome was driven over 4x4-type timbers spaced a
few feet apart. It was followed by a different brand of motorhome, which
was fitted with a cover to obscure its manufacturer's name. This
demonstrated the difference in suspension abilities. The GMC handled the
timbers with ease; its tires danced over the obstacles with the body
barely bouncing. The covered motorhome with leaf-spring suspension on a
competitor's chassis had its tires leaving the ground and appeared to be
leaping in the air after the third or fourth timber was crossed -- much to
the crowd's delight.
Alex Birch, foreman of the Experimental
Engineering shop, was the driver of the GMC in many of these
demonstrations. At one demonstration, he completed the pass, pulled up
smartly in front of the grandstand, and was to open the door, wave at the
crowd, and then drive off. All went well until the door latch jammed and
the door could not be opened. Alex's quick thinking saved the day,
however. He hopped back in the driver's seat, honked the horn, waved to
the crowd, and drove off. That was not the last of the problems associated
with the latch manufactured by Lake Center Industries, which was used in
the 1973 motorhomes.
Dolly Cole, wife of GM president Ed Cole,
and friends went to a charity ball one evening at the Detroit Orchestra
Hall. They chose to arrive in the new GMC Motorhome to show it off. The
driver pulled the coach up in front to discharge the passengers, and the
door latch jammed again. The passengers disembarked with great difficulty,
which the press attending the event duly noted in the morning papers.
Early that next morning motorhome engineers were called into Alex Mair's
office and told in no uncertain terms to fix the problem, immediately.
That is why you see a stainless-steel patch with the replacement latch on
1973 GMC Motorhome doors up to approximately serial number 3V101850.
Starting in 1973 and continuing through
1977, a number of films were produced to promote the GMC. Walking into a
GMC Motorhome dealership showroom, you might see what looked like a small
TV with a number of film cassettes. GM called these units "Mini-Theaters,"
and films showing the many features of the motorhome could be viewed on
one of these self-contained units. Fourteen films were produced, as well
as three more from a TV program of the time, "Holiday on Wheels."
In late 1973, the 1974 models were
introduced with little fanfare. They were a continuation of the previous
year's models, incorporating running changes made to correct deficiencies
in the early designs. Many of these changes and corrections can be found
in the GMC Motorhome Service Bulletins and other publications. One change
for the better with the 1974 models, in my opinion, was the discontinuance
of the parrot green color.
The GMC plant was operating at one shift
while the Gemini plant was at two shifts. The motorhome's body and chassis
were being assembled more rapidly than the interior upfitting at Gemini.
An early problem at the Gemini facility was plant layout: parts and
assemblies were not properly placed for efficient manufacturing flow given
the relatively large build volumes. Gemini plant personnel experience had
been based on the one-at-a-time build practices at Travco. Employees from
the GMC plant were able to provide assistance with this problem, thanks to
their extensive background in large-volume manufacturing.
The parking lot at the Gemini facility in
Mount Clemens was usually full of motorhomes awaiting interiors. Completed
coaches were shipped from this location to dealers as well.
The GMC Motorhome assembly operations were
shut down in early December 1973. The official reason was "to bring
inventories in line with retail sales." However, the gasoline shortage had
begun to seriously affect the RV industry.
In Las Vegas in January 1974, GMC announced
a new series of vehicles for commercial, medical, and general
transportation purposes, and nine Transmode concept vehicles were shown to
the press. An Eleganza SE (RPO#696) "featuring customized interiors much
more luxurious than those in current models" was displayed as well. This
was the start of Alex Mair's plan to make the GMC Motorhome the "Cadillac
of motorhomes." He had made the comment at one point that the GMC
Motorhome was to GMC what the Corvette was to Chevrolet, its halo (image)
vehicle.
GMC, now offering a motorhome rental
program, conducted a fuel economy run with press representatives from
Automotive News, Motor Trend, and Trailer Life
magazines. A motorhome economy run could be very risky, and some reporters
noted that GM should get the "sheer courage award" and had "corporate
guts" to propose an economy run on a 23-foot motorhome during the gas
crisis. Over a 264-mile test from Los Angeles to Las Vegas, which included
the well-known Baker Grade, which peaks at 4,751 feet, the reported
mileage was 10.2 mpg using cruise control most of the way. The return trip
provided an 11.2-mpg average, since this direction was slightly more
downhill. As can be seen by the above efforts, GMC was trying hard to
revive sales during this period of gas shortages.
In March 1974 GMC announced that it had
suspended production once again due to a lack of orders. Gemini still had
a backlog of shells to upfit, but scaled back to a one-shift operation.
Sales began picking up over the next couple of months, and by midyear
inventories were depleted and production was resumed.
The 1975 model year brought many changes to
the GMC Motorhome. New model names were announced; Eleganza II and Palm
Beach replaced the previous models. New, better-quality woven fabrics
supplanted the printed fabrics that had been used in earlier coaches, and
Flexsteel seating was installed. Assembly of interiors at Gemini was
discontinued, and all of the interior upfitting was brought in-house at
the Pontiac plant (none of the Gemini employees were picked up by GMC for
the in-house assembly). Grand Rapids Furniture Co. was now building the
interior modules, and dovetail joints replaced glue and staples. While the
quality of the interior fittings improved measurably, heavier weight and
higher cost of the furniture was the downside. Exterior changes included
new colors and stripes; exterior paint was now urethane (Imron) instead of
the previously used synthetic enamel; raised "GMC" letters replaced vinyl
decals on the motorhomes; and the fit and function of exterior panels and
doors were improved, as was the floor substructure. Stronger frame cross
members were added; new Hehr side windows were installed; an HEI ignition
system was added; and polybutylene (plastic) plumbing replaced copper.
Gross vehicle weight ratings were increased to 11,700 pounds, and many
other changes and improvements were incorporated as well.
The Transmode, an "empty motorhome" for
those who wanted to build their own interiors, was available from 1975
through 1978. GMC no longer offered the 23-foot unit as a motorhome,
although it could still be purchased as a Transmode and upfitted by
others.
Many companies were upfitting the new Transmode as motorhomes and for
commercial applications. Some of the motorhome upfitters were Avion,
Coachmen, Carriage, LRP, Midas, Norris, Hughes, Landau, Roll-a-long, El
Dorado, Foretravel, and Winnebago, plus a few others with very low build
quantities.
Transmode upfitters for commercial purposes
were many. These GMCs were used as ambulances/emergency vehicles,
bookmobiles, mobile banks, airport shuttle buses, mobile showrooms,
on-location radio broadcast centers, hearses, courtesy coaches for beer
and soda distributors, and much more.
The 1976 GMC Motorhome models arrived with
few changes from the previous year. Two new models were introduced in
addition to the Eleganza II and Palm Beach carryovers: the Glenbrook and
Edgemont. The Edgemont was the price leader with a base price about $1,000
below the other three models. Running changes continued to be made, most
starting with serial number 6V100878. They added an entry door strap;
relocated the air compressor and solenoid valves to an inside compartment
(Electro Level); and added a glass-lined hot water tank, cab floor support
(stamping), radial tires/wheels, and body side rub molding (with adhesive
replacing stainless).
In 1977 the Kingsley model debuted,
replacing the previous year's Glenbrook model. The Eleganza II and Palm
Beach continued to be offered. The Edgemont was replaced by a new twin
bed/dry bath floor plan in the Eleganza II. Other changes included a
redesigned dash, which relocated the AC/heater outlets and moved the
Electro Level controls to the left of the driver; a new Freedom battery;
an entrance door rain cap; and an assist handle.
Another model, the Coca-Cola, was built in
two versions. The first was the "standard" model, offered in cameo white
with a red horizontal stripe, the same pattern as other GMC Motorhomes. It
is believed these motorhomes were used primarily by Coca-Cola bottlers and
distributors as courtesy coaches and at public events. The second
Coca-Cola model was dubbed the GadAbout and equipped with all the bells
and whistles. The exterior paint was white with a sweeping wedge of
Coca-Cola red up the sides that blended to a yellow near the top rear of
the coach. The GadAbout name appeared near the front, and a
bottle-cap-shaped spare tire cover was at the rear.
Inside, the Coca-Cola red upholstery was
the same in both coaches. In the GadAbout, refrigerator door graphics made
the appliance look like a soda-dispensing machine -- very impressive! Other
extras were a Coca-Cola logo entry floor mat, clock, and mirrored picture,
as well as a rear table with a Coke checkerboard pattern. On the dash
above the glove box was an attractive pewter plaque with a GadAbout
motorhome in profile and the slogan, "Coke adds life to . . . cruisin' in
a GadAbout."
Five GadAbouts were given away to
first-prize winners of a Coca-Cola contest held in December 1977.
Twenty-five second-prize winners each received the use of a GMC Motorhome
for two weeks along with $3,000 in cash. GMC records indicate that a total
of 55 Coca-Cola models were built, most in 1977 and a few in 1978. It was
originally believed that only five of the total were GadAbouts; however,
more have been discovered lately, and as many as nine or 10 may have been
built.
The 403-cid engine replaced the 455-cid
engine by the end of January 1977 and was used for all remaining motorhome
production. GM's downsizing had started and would soon have severe
implications for the GMC Motorhome.
Plant No. 3 in Pontiac, Michigan, had been
the site of GMC Motorhome production from the beginning in late 1972
through mid-1977. In August 1977 production was moved to Plant No. 29,
also in Pontiac. This site provided a more efficient production facility
and was used through the end of production in 1978.
On November 11, 1977, Robert W. Truxell,
general manager of GMC Truck and Coach, announced the phaseout of GMC
Motorhome and Transmode production (see the accompanying sidebar for the
text of the announcement). According to the GMC engineers I have spoken
with, no advance warning was given to the employees, and they were
surprised at the news. In all probability, it should not have been too
surprising. Carrying too much burden and overhead and never reaching the
volumes needed to achieve real profitability, GM saw better ways to use
its resources and achieve greater return on its investment.
The 1978 model year began with three models
of GMC Motorhome interiors: Eleganza II, Palm Beach, and Kingsley.
Production of the Transmode continued as well, with many upfitters
participating. The major upfitter was Coachmen Industries (Jimmy Motors),
producing the Royale (26-foot) and Birchaven (23-foot).
New GMC Motorhome two-tone body colors and
a three-color horizontal midbody stripe distinguished the 1978 models from
other years. A number of features that were options in previous years were
now standard, and many features were improved. Improvements included the
Electro Level II, a larger bathroom skylight, a 36-gallon holding tank,
integral refrigerator vents, new solid cupboard doors, new countertops,
and woven window blinds. Chrome bumpers were finally standard. Among the
new options were a glass and spice rack, a microwave oven, an overhead
rear cabinet, a six-speaker sound system, a lighted visor vanity mirror,
and a lockable overhead front cabinet.
On the Transmode, urethane foam floor
insulation, previously an option, was now standard. The steering wheel,
column, and hand brake were now saddle-colored, and the front-end GMC logo
was now displayed in raised lettering instead of a decal.
With the end of production approaching,
plans had to be made to phase out production in as orderly a manner as
possible. Build-out plans were made, i.e. matching parts inventories to
dealer/customer orders. One example of this was the sale of surplus
transmissions and final drives by GM to an Ohio GMC Motorhome dealer who
purchased 1,361 units. These were initially offered at a sale price of
$495 each (the suggested list prices were identified as $1,375 for the
transmission and $675 for the final drive). When the inventory got down to
500 units, the sale price was reduced to $475. In 1983 the price was
reduced again to $295, at which time the remaining inventory was sold. GMC
Motorhome and Transmode production ended in July 1978.
That being said, the rest of the story is
as follows. An important consideration should be that Alex Mair, a very
strong advocate for the GMC Motorhome, had gone to the Pontiac Division,
and there was no one willing to fight for the program. There were, of
course, other serious and obvious concerns with the program that needed to
be resolved. The Oldsmobile engine and drivetrain would soon be gone from
the Oldsmobile lineup due to GM's downsizing efforts. GMC would either
have to build this unit on its own or design a new one involving new
tooling and development expenses. Sketches of a rear engine/rear drive and
front engine/front-wheel drive (using a transfer case) exist. A front
suspension using a solid front axle and single leaf springs with an air
spring at the center, similar to the RTS bus design, was proposed.
Apparently, one operational prototype of a transverse front
engine/front-wheel-drive motorhome was built. None of these redesigns
would support a business case. Motorhome build quantities were just too
small to end up with positive results and, finally, the decision to
terminate production ended all further development efforts.
GM announced additional details over the
next few weeks. The GMC Motorhome Club, supported by GM, was discontinued,
and in its place a new organization, GMC Motorhome Owners Association (GMC
MOA) was formed. GM noted that it was independent and separate from GMC
Truck & Coach.
GMC attempted to sell the GMC Motorhome
assets for a reputed $7 million to another manufacturer that would
continue production. AM General, a Division of American Motors, took a
look and built five prototypes using a 454-cid engine, with a transfer
case to turn the drive back to the new front axle, much like Revcon
actually did in subsequent years. On the inside, the front steps to the
driving compartment had to be modified to allow additional room for the
transfer case. This was as far as it went for AM General. After some
testing, company officials decided not to pursue the purchase of the GMC
Motorhome.
Eventually Donald Wheat purchased the
motorhome manufacturing rights and tooling. Mr. Wheat organized the Wheat
Motor Company (WMC), and several ex-GM officials served as corporate
officers. The company was to be based in Rancho Cucamonga, California. It
was reported initially that the use of a GM 454-cid engine was planned;
that later changed to a Ford 460-cid engine. The WMC Motorhome was to be a
1986 model and retail for about $60,000. The difficult and expensive
redesign of a new engine and drivetrain by a company with fewer resources
than GM doomed the effort, and no actual production took place.
The end? Hopefully not. Long Live the
GMC
GMC Motorhome Phaseout
A press release datelined Pontiac,
Michigan, November 11, 1977, read as follows:
GMC Truck & Coach Division of General
Motors plans to discontinue producing luxury Motorhomes and similar
Transmode multipurpose vehicles and convert those plant facilities to
expand truck operations, a GM vice president said today. Robert W. Truxell,
general manager of GMC Truck & Coach said, "As a result of this action,
GMC will be able to utilize production facilities more effectively for
servicing growing truck demands. The long-term outlook for greater truck
activity is extremely bright and GMC production operations will be
realigned to help meet expanding customer needs," he said.
"GMC will continue offering a wide range of
trucks which are designed to meet a variety of recreational vehicle
applications," Truxell emphasized.
He described the planned facility
conversion program as "a continuation of major steps taken recently at GMC
Truck & Coach facilities in Pontiac in response to growing truck needs.
Van production will be doubled to more than 250 a day on two-shift
operations, starting this month.
"With a continuation of strong sales, GMC
van operations will be expanded throughout the 1978 model year," Truxell
pointed out. He said another van production increase is anticipated in the
spring of 1978 and facilities are being expanded to begin van interior
installation operations in the spring.
The GMC van program has already added about
1,000 jobs in Pontiac, and another 1,200 new jobs could result within a
year, Truxell said.
A high percentage of GMC's chopped van
output is utilized for recreation vehicle applications with special
bodies, such as mini-motorhomes, installed by independent companies.
"While it is regrettable that luxury Motorhome and Transmode production
will be discontinued, the action will assist GMC in serving other parts of
the recreation vehicle business to a greater extent and help meet growing
truck demands," Truxell explained.
He said industry truck sales in the United
States in the 1978 model year should reach 3,750,000 units, and
anticipates the growth trend will continue.
GMC Motorhomes have been built in Pontiac
since their introduction in early 1973. Parts, service, and warranty
provisions will continue through existing GMC Motorhome dealerships,
Truxell said.
Termination of Motorhome production will be
accomplished gradually and it is expected that approximately 325 persons
currently involved in Motorhome activities will be transferred to other
GMC Truck & Coach operations, Truxell said.
|
GMC Motorhome
Production Totals |
| |
Model year
production: |
|
|
|
| |
1973 |
1974 |
1975 |
1976 * |
1977 |
1978 |
| 23' |
461 |
168 |
~ |
~ |
~ |
~ |
| 26' |
1,598 |
1,496 |
1,195 |
2,413 |
1,695 |
689 |
| Transmode
23' |
~ |
~ |
36 |
549 |
253 |
178 |
| Transmode
26' |
~ |
~ |
425 |
298 |
455 |
1,012 |
|
Total: |
2,059 |
1,664 |
1,656 |
3,260 |
2,403 |
1,879 |
| |
|
|
|
* peak production year |
