Reigning champions Vauxhall stayed on as one of the two remaining manufacturers, dropping its Astra Coupe after four straight titles with the chassis, and introducing the all new Astra Sport Hatch (again prepared by Triple 8). Reigning champion James Thompson had left the BTCC to contest the World Touring Car Championship with Alfa Romeo, leaving the 2004 runner-up and 2003 champion Yvan Muller to head the team. SEAT Cupra Cup graduate Gavin Smith joined the team after appearing in an Astra Coupe for GA Motorsport at one meeting in 2004, and Colin Turkington moved into Thompson's seat after two promising seasons with the WSR MG squad.
