Although founded as a car maker, they were major suppliers of vehicles to British Armed Forces during World War I, and in the 1920s moved into bus manufacture.

Critchley left the company in 1906 and was replaced by the team of Walter James Iden, A. W. Reeves and Hubert Woods who introduced the 12-14hp (later 15hp) and 20hp models.

Production was originally in the Crossley Brothers factory in Openshaw, Manchester but in 1907 moved to a nearby site in Napier Street, Gorton.

In 1938, the eastern side became another aircraft factory, this time managed by Fairey, and after World War II, it became the final home of Crossley Motors.

Re-armament work caused the search for more space and in 1938 a factory was opened in Greencroft Mill, Hyde, about 3 miles (4.8 km) east of Errwood Park.

As well as Munro, Harry Ingle, Jack Halstead and Fred Flood were active in the Plebs League and part of the Crossley Shop Stewards Committee.

The outbreak of World War I resulted in a rapid expansion of the RFC, and by 1918 they had over 6,000 of the vehicles with staff car, tender (light truck), and ambulance bodies.

Crossley 25/30 hp Tenders were used by British paramilitary police ("Black and Tans" and the Auxiliary Division) in Ireland during the Irish War of Independence (1919–1922).

[7] The National Army of the new Irish Free State continued to use them for troop transport throughout the Civil War period, but they were worked hard: of 454 originally supplied,[when?

[citation needed] The 20/25 model was also the first vehicle to be supplied to London's Metropolitan Police Flying Squad in 1920, some of which were fitted with radio equipment.

Two Crossley trucks based on the 25/30 car chassis were from 1924 to 1926 the first vehicles to be driven from Cape Town to Cairo by the Court Treatt expedition.

[8][9] A range of heavy goods vehicles starting with the 1931 diesel-powered 12-ton payload Atlas was announced but only a few were made as the factory was by then gearing up to concentrate on buses and military orders.

From 1936 military production was rapidly ramped up with British re-armament at first with "IGL" models but from 1940 with a four-wheel drive "FWD" chassis in both tractor unit and truck form.