Foers Engineering’s hard-as-nails Ibex range is now available with a 3.2-litre diesel engine from Austrian manufacturer Steyr Motors.

This compact six-cylinder block apparently has a particularly high power-to-weight ratio that suits the vehicles’ off-road bent, delivering 272hp/610Nm all told.

It is also capable of running on various fuels without any impact on performance, including – once calibrated – light heating oils and biofuels.

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Plus, it can handle extreme temperatures, altitudes and deep fording, is designed to operate on steep inclines, and will tolerate high shock loads – including parachute drops.

As each vehicle is built to a custom spec, buyers have plenty of other options in the powertrain department – starting with second-hand Land Rover 300tdi or TD5 units.

Alternatively, there’s a 3-litre, six-cylinder BMW diesel, GM’s 430hp V8 petrol, or a battery-electric setup.

Allied to one of these is a manual or automatic transmission paired with a two-speed transfer case and lockable or limited slip differential.

Both the four- and six-wheelers get a heavy-duty galvanised chassis and cabin monocoque, wrapped in aluminium body panels that are both bonded and riveted in place.

Payload capacity starts at 1.5t, they’re rated to tow 3.5t, and there is a range of chassis sizes and body configurations to suit the vehicle’s end use.