Contemporaneous with the Greyhound-exclusive Scenicruisers, GM manufactured the single-deck "Highway Traveler" (PD-4104) parlor from 1953 to 1960, pioneering the monocoque structure, air suspension, and slanted side windows that would go on to be used on the well-known New Look transit buses.

[3]: 222, 314 The GM New Look Transit Coach series (nicknamed "fishbowl" for the six-piece rounded windshield) was introduced in 1959.

One of the product designs developed in response to this market demand was the GM "Buffalo" bus, nick-named for the hump-back style of the roofline.

Many features such as the split-level design from the Scenicruiser and the revisions introduced in the PD-4106 model were included in the Buffalo bus.

The difference in the height of the front and rear roof was approximately one foot, giving a sleeker, more aerodynamic shape.

The entire engine–transmission–radiator assembly was mounted on a cradle which could quickly be removed and replaced for maintenance, allowing the bus to rapidly return to revenue service while leaving the powertrain in the shop for repairs.

[1]: 317  The 4107 and 4903 models were notorious for being difficult to shift through the gears, often making loud, grinding noises that tended to upset the passengers.

The biggest complaint about the 4905 and 4903, from the drivers' point of view, was that the extra 5 feet (1.5 m) of length was all between the front and rear axles.

[4] The GM Buffalo models were purchased primarily by affiliates of the National Trailways Bus System and many other smaller operators.

In the 1970s, MCI products began to overtake the GM Buffalo models in sales volume, especially after the introduction of the popular MC-8 at the Transpo 72 exhibition held at Dulles Airport near Washington, DC, in 1972.