I think you will find the registration number is J113AEV
Added by Adrian Carmichael on 06 September 2022.
You can actually have duals on 4X4, 6X4, 6X6 or any multi axle vehicle, if you need the extra tonnage on the rear axle or axles, and their are loads of examples on this site.
BUT the big advantage of the single rear wheel arrangement is that it tracks the front wheels, which is a huge advantage in mud or snow -and on rutted tracks or unmade roads with major variations in surface levels. This is why very few military designs have duals, and why most brush pumpers are equipped with single rear wheels.
Added by Jeff on 07 December 2012.