A heavier, more rugged development of the earlier Lanchester 4x2 armoured car, it remained in service with Territorial and colonial units until the early 1940s and saw action in the Battle of Malaya.

[1] In both marks and all versions the Lanchesters featured the same basic functional arrangement: a frontal engine compartment; a main fighting compartment mounting a fully traversing turret; and rear equipment stowage; a two-man turret mounting one .5 inch (12.7 mm) and one .303 inch (7.7 mm) Vickers machine guns co-axially; and fitted with a cupola that could be independently rotated, greatly aiding observation while hatches were closed.

Lanchesters had good cross-country performance (particularly in the new 6×4 form), they were considered reliable and easy to maintain but proved too big, too top-heavy and too slow for the reconnaissance missions for which they were originally conceived.

In January 1929 the first Lanchesters (and Rolls-Royce armoured cars transferred from Navy and Air force stocks) were received by the 11th Hussars regiment as part of its mechanization from horse-mounted cavalry.

10 Lanchesters were given to the Territorial Army (23rd London Armoured Car Company and 1st Derbyshire Yeomanry) and in 1940 one was converted to provide protected transportation for use by Cabinet ministers and other VIPs.