The large operator West Midlands Passenger Transport Executive was created in 1969, being the first of several PTEs around the country designed to integrate all public transport in their areas. The municipally owned corporation buses of Birmingham, Walsall, West Bromwich and Wolverhampton were transferred to the new PTE, followed by those of Coventry in 1974. Services between those towns and cities and in other West Midlands towns were run by Midland Red, by then owned by the National Bus Company. The PTE purchased those local services, and the depots and buses required to run them, in December 1973. Midland Red thus lived on but many of its employees and 413 of its buses joined the PTE.

Bus 4871 had been built by Midland Red itself and was an early example of its splendid D9 design, in production from 1960 to 1966. It entered service from Stourbridge garage in July 1960. Despite all the changes reshaping the industry, 4871 remained at Stourbridge until a major engine failure ended its career in August 1977. The Museum's predecessor society purchased it in October on the basis of good body condition, together with a replacement engine. Subsequently the Museum acquired another D9 in Midland Red colours so 4871 is to retain blue and cream to represent the buses that passed to WMPTE.