Will and Kirsten test-drive a tree harvester deep in the Uruguayan forest.

Will Mellor and Kirsten O'Brien learn to drive and race the gravity-defying Snow Groomer.

Will Mellor and Kirsten O'Brien learn to drive and race the 47-tonne, go-anywhere Arktos.

Will Mellor and Kirsten O'Brien learn to drive and race the Terex TR100, a dumper truck the size of a house.

Will Mellor and Kirsten O'Brien learn to drive and race the multi-storey mother of all vehicles, standing 15 metres high and the powerhouse of the docking industry - the straddle carrier.

Will Mellor and Kirsten O'Brien learn to drive and race the the Romanian Army's frontline combat tank, the TR-85.