Found this on web re colours for RAF vehicles:
RAF vehicles:
[Pre-1941 - Blue/grey. About time of the Battle of Britain (summer 1940) they started camouflage painting them.]
Blue/grey. From Aug 1941 - Khaki Green No. 3 on top of which a disruptive pattern of paint Nobels Tarmac Green No. 4 or Light Green No. 5.
From August 1942 - Camouflage Green No. 3 on top of which a disruptive pattern of paint Dark Tarmac No. 4 is applied.
From December 1942 - Paint Camouflage Brown Special No. 2 on top of which a disruptive pattern of paint Dark Brown is applied.
From September 1943 - Paint Anti-Gas M. T. [Motor Transport] Brown Special No. 2 on top of which a disruptive pattern of paint Dark Brown is applied.
This was soon changed to paint Anti-Gas Olive Drab on top of which a disruptive pattern of paint Black matt finish is applied.
From September 1944 - Paint Olive Drab without any disruptive pattern.
In 1944 upper surfaces of any vehicles regularly used within the landing area of airfields are to be painted yellow.
Until the end of the war an area of Gas Detector paint irregular in shape approximately 36 inches square to be applied to each front mudguard or a panel so placed as to be visible by the driver.
From April 1946 Blue/Grey on bodywork with wings (fenders) , chassis and valances in paint semi gloss Black.
ALL RAF vehicles to be camouflage painted except Air Council and A.Os. C. (Air Officers Commanding), vehicles hired locally and Works Department vehicles working on aerodromes.
NOTE: Changes were gradual, as vehicles needed repainting.
RCAF basically followed the British colour schemes as far as I know. IN Canada they did not go to the camouflage painting scheme, but had the black fenders.