This is one of a large number of double deck buses that took part in the Greater Manchester Transport Society's Trans Lancs Historic Vehicle Rally in September 1993 in Heaton Park, Manchester.
It's a 1949 (though the programme of the event says 1948) Crossley DD42 from the Society's museum. The programme gives this information about the vehicle:
'Crossley DD42/8S, Crossley H30/26R, 1948 JND791
Manchester City Transport 2150
Entered by Greater Manchester Transport Society
The sole survivor of a once numerous fleet of Crossley vehicles which graced the
streets of Manchester during the 1950s and 1960s. A star attraction at the recent
Crossley Weekend held at the Museum of Transport.'
Next to the Crossley is another of the Transport Museum's vehicles, a 1951 Leyland PD2/3, fleet number 3245 and registration JND646.