US GMC PD-3751 "Silverside Trailwagon" Trailways Company.

Intercity bus designed in the mid-1930s by Yellow Coach for one of the largest US coach companies, Greyhound Lines. The bus was a revolution in auto construction; corrugated aluminium and plastic materials were widely used in its build. Special attention was paid to maximum comfort for passengers. Following the construction of a wide network of high-quality highways during the Great Depression, rail passenger traffic almost stopped due to its inability to compete with high speed road transport. Series construction was undertaken at the Pontiac West Assembly plant in Pontiac, Michigan, where General Motors built pick-ups and trucks. In addition to Greyhound Lines, buses of this type were used by other national carriers such as Trailways Travels. Silverside bus operations continued almost until the end of the 1950s, after which a large number were sold to other countries, notably in Latin America.

Markings for Trailways bus with San Francisco destination.