Wheels revolve around pins called axles. A single axle holds two wheels together; a tandem axle holds two sets of wheels closely together. Unless your trailer or caravan is more than 17 feet long, axle choice is a matter of preference.
Single axles maneuver more easily and weigh less than tandem axles. Since single axles must carry less weight than a tandem axle, singles make for better fuel economy and less towing wear-and-tear.
Tandems have more stability and straighter tows than single axles, which tend to sway without a sway control device. Four tires limit the tandem's turning radius and cost more to replace than single axles.
Tandem axles cost more than singles as they support twice as many tires. When choosing one type over the other, keep in mind that your suspension should be in tip-top shape as it affects your tow ride.
