The Length Of A Vintage Gmc Bus Explored

The GMC PD-4103 was a single-decker coach built in the United States in 1951 and 1952. It was an improved version of the earlier PD-4102 transition model, with a new front end, redesigned rear end, and various body, mechanical and electrical improvements. The PD-4103 was 35 feet (11 m) long, 96 inches (2.4 m) wide, and 115+11⁄16 inches (2.938 m) high. It was replaced by the PD-4104 Highway Traveler in early 1953.

The GM PD-4103 was a single-decker coach built by GMC in 1951 and 1952

The GM PD-4103 was a single-decker coach built by GMC in the United States in 1951 and 1952. It was a 37- or 41-passenger Parlor-series highway coach and was an improved version of the earlier PD-4102 "transition" model.

The PD-4103 was the last in a series of low-budget "conversion" parlor coach models, based on the basic Yellow Coach/GM Truck and Coach transit bus models which first appeared in 1940. The PD-4103 was 35 feet (11 m) long, 96 inches (2.4 m) wide, and 115+11⁄16 inches (2.938 m) high. It had a GVWR of 30,000 pounds (14,000 kg), a front GAWR of 11,000 pounds (5,000 kg), and a rear GAWR of 19,000 pounds (8,600 kg).

A total of 1501 PD-4103 coaches were built, with 900 built in 1951 and 600 in 1952, plus one that was converted by GMC from a PD-4102. The PD-4103 competed directly with, and surpassed in sales, a similar model from ACF-Brill Corporation, the IC41.

The PD-4103 incorporated several improvements over the PD-4102, including a rear luggage bay door on the left side, an improved refrigeration system, and a new, higher-rated Delco generator. It also offered optional facilities for a restroom or a food buffet, a feature used on many cars ordered by Trailways.

In early 1953, the PD-4103 model was replaced by the groundbreaking PD-4104 "Highway Traveler", which pioneered the monocoque structure and air suspension.

The PD-4103 was replaced by the PD-4104 in 1953

The GM PD-4103 was a single-decker coach built by GMC in the United States in 1951 and 1952. It was an improved version of the earlier PD-4102 "transition" model, featuring a new rear end design and improved mechanics and electronics. The PD-4103 was 35 feet long, 96 inches wide, and 115+11⁄16 inches tall, with a GVWR of 30,000 pounds. It was powered by a Detroit Diesel 6-71LA39 engine and offered with either a manual or automatic transmission.

In early 1953, the GM PD-4103 was replaced by the groundbreaking PD-4104 "Highway Traveler". This new model featured a monocoque body, improved air conditioning, commodious luggage bays, and an air suspension system. The PD-4104 was also wrapped in a sleek, modern design that matched the look of the later PD-4501 Scenicruiser. While the PD-4103 was already an improvement on previous models, the PD-4104 took things even further, offering a superior ride and handling experience that set a new standard for passenger and operator expectations.

One notable improvement of the PD-4104 over the PD-4103 was the restroom design. The PD-4103 had a problematic restroom with limited headroom due to the overhead refrigeration unit and engine air intake. The PD-4104 rectified this issue, setting a new pattern for bus restrooms that would be followed by all manufacturers for the next 50 years.

In terms of sales, the PD-4103 competed directly with the IC41, a similar model from ACF-Brill Corporation. Despite the competition, the PD-4103 surpassed the IC41 in sales. This was due in part to the much more efficient GM Diesel 6-71 engine used in the PD-4103, which offered better fuel economy than the IC41's Hall-Scott 190 engine.

While the introduction of the PD-4104 made the PD-4103 instantly obsolete, the older model continued to be used in scheduled and charter service for another two decades. Many PD-4103 buses were still in operation with small charter operators into the mid to late 1970s.

The PD-4104 was also known as the Highway Traveler

The PD-4104, also known as the "Highway Traveler", was a groundbreaking highway coach model introduced by GMC in 1953. It replaced the GM PD-4103 model, featuring significant improvements in design and performance. The PD-4104 was wrapped in GM's version of Raymond Loewy's "Highway Traveler" concept, sharing styling features with the later PD-4501 Scenicruiser, another exclusive model for Greyhound Lines.

The PD-4104 offered a modern, sleek appearance and improved engineering. It built upon the previous PD-4103 model, enhancing the air conditioning system, suspension, and luggage bay capacity. The air conditioning system utilised an underfloor evaporator in conjunction with heater cores, providing excellent temperature control. The new air suspension system, using common parts with 1953 transit models, offered superior ride and handling compared to its predecessors. The elimination of the traditional longitudinal steel frame allowed for commodious luggage bays, further enhancing the traveller experience.

The PD-4104 set new standards for bus restrooms, influencing designs for the next 50 years. It addressed the headroom restrictions in the PD-4103 by repositioning the refrigeration unit and engine air intake. This model also retained the optional restroom and food buffet facilities, a feature first introduced in the PD-4103.

The PD-4104 was a heavy reworking of Greyhound Lines' previous PD-3751/PD-4151 models, with several structural members remaining identical. Initially, it utilised the same Continental/Ingersoll-Rand engine/refrigeration compressor assembly as its predecessor, later transitioning to the more reliable and higher-capacity Waukesha/Trane engine/compressor combination. This change ensured that the PD-4104 could handle even the hottest and most humid climates with ease.

The PD-4104 was the last GM coach to employ a separate engine for refrigeration. Its introduction rendered the PD-4103 model obsolete, although the latter continued to be used by operators like Pacific Greyhound Lines for another two decades. The PD-4104's modern design and improved features played a role in ACF-Brill Corporation's decision to exit the bus-building business in 1954.

The PD-4104 was superseded by the PD-4106 in 1961

The PD-4104 was a groundbreaking model that superseded the PD-4103 in 1953. It was a single-decker coach built by GMC in the United States. The PD-4104, also known as the "Highway Traveler", was a significant improvement over its predecessor. It featured a monocoque body design, eliminating the traditional longitudinal steel frame. This innovation resulted in a much improved air conditioning system, spacious luggage bays, and an advanced air suspension system.

The PD-4104 set new standards for bus design and comfort. It offered an excellent temperature control system, achieving superior ride and handling compared to older models. The PD-4104's sleek and modern appearance, shared styling features with the later PD-4501 Scenicruiser, another exclusive model. This model was also notable for setting the pattern for bus restrooms, influencing the designs of all bus manufacturers for the next 50 years.

The PD-4104 was a heavy reworking of the previous PD-3751/PD-4151 models, with several structural members remaining identical. Initially, it utilised the same Continental/Ingersoll-Rand engine/refrigeration compressor assembly as its predecessors, but soon transitioned to the more reliable and higher-capacity Waukesha/Trane engine/compressor combination. This new combination was rated at a nominal six tons and could easily overcome hot and humid climates.

The PD-4104 was the last GM coach to use a separate engine for refrigeration. While it rendered the PD-4103 obsolete in 1953, the older model continued to be used in scheduled and charter services for another two decades. The PD-4104's improved features, engineering, and modern appearance played a role in ACF-Brill Corporation exiting the bus-building business in 1954.

The PD-4104 had a larger-windowed big brother, the PD-4105 Scenicruiser

The 1953 GMC bus, known as the PD-4104, was a groundbreaking model that replaced the earlier PD-4103 in 1953. It featured a sleek, modern design and offered improved air conditioning and luggage bay capacity. The PD-4104 also had a larger-windowed big brother—the PD-4105 Scenicruiser.

The PD-4105 Scenicruiser was a significant upgrade from the PD-4104, boasting even bigger windows that offered passengers panoramic views of their surroundings. This model truly lived up to its name, "Scenicruiser," by providing an enhanced visual experience while cruising along various routes. The PD-4105 was also longer than the PD-4104, measuring 40 feet in length. This extra length provided more spacious interiors and additional seating capacity.

The PD-4105 Scenicruiser was an exclusive model for Greyhound Lines, one of GMC's favoured customers. The partnership between GMC and Greyhound Lines played a crucial role in the development and success of these coaches. Greyhound had significant influence over the design of the PD-4105, ensuring it met their specific requirements and standards.

The PD-4105 Scenicruiser set a new standard for bus design and comfort. Its innovative features and spacious interiors made it a popular choice for long-distance travel. The model's impact extended beyond just GMC and Greyhound, as it influenced the bus designs of other manufacturers during that era. The PD-4105's combination of style, functionality, and comfort contributed to its enduring legacy in the history of road transportation.

Overall, the GMC PD-4105 Scenicruiser represented a significant evolution in bus design, building upon the foundation laid by the PD-4104 and taking road travel to new heights of comfort and visual appeal. Its impact on the industry and the travelling public cannot be overstated.

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