At the height of WWII, in 1942 - 1943, the engineers behind the SARC sought to improve the vehicle’s capabilities in an effort to match the German Sd.Kfz. 234. To that extent, the engineers developed the heavier, 8-wheeled experimental Mark V variant, followed by the improved Mark VI prototypes.

Only two prototypes of the SARC Mk.VI were built, one being armed by a 2 pdr and the other with a 6 pdr gun. While the former was sent to the UK for testing, the latter remained in South Africa. Despite favorable test results, the increased availability of more suitable American armoured cars in the later stages of the war made the Mark VI somewhat redundant and further development was cancelled.