I don't have a clue....But most 4 wheel vehicles have 6 wheels, 4 on the road, 1 spare and 1 to steer with...
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Don't take life too seriously.... No one gets out alive
KIA Sorento CRDi EX ( Ebony black) with 5 hex chrome plated tire air valve covers, Coramal Sunsheild, Elcheapo GPS, First Aid Kit, full KIA toolkit & Yellow lenses on the Foglights......
This term is derived from the old Wheelwright's (Waggon Builders) term for the fore carriage turntable. The front wheel unit of a horse drawn, four wheel Lorry, Dray, Wain, Truck, Float, Caravan, and so on, is mounted on a simple pair of flat iron rings in a mechanism known as "the Fifth Wheel". Like a flat wheel, the rings slide on each other allowing the forcarriage wheel unit to pivot. The forecarriage is attached to the horse shafts and pivot as the horse/s turn.