Roadwheels were crucial to a tank's mobility. Indeed the loss of any one roadwheel could render a tank useless in combat.

Both the Germans and the Soviets took measures to ensure that the roadwheels and the rest of the suspension were protected. The Germans, for example, added Schurzen to their tanks. But nothing could stop the occasional mishap, and it soon became apparent that tanks would have to sport spare roadwheels.

Spare roadwheels were often bolted or jerry rigged onto whatever part of the tank was suitable, and allowed quick replacement of a damaged roadwheel. Spare roadwheels also offered some protection against enemy fire, and thus were often placed around the weakest parts of the tank.

Due to their large size and the small likelihood of having to replace a roadwheel, most tanks sported only one or two spare roadwheels.

WHERE TO LOOK FOR A SPARE ROADWHEEL

Look for a roadwheel that is out of place (i.e. not with the roadwheels that make up the suspension).