What is a tandem axle?

A tandem axle is a suspension system consisting of two axles placed one behind the other, usually with four or six wheels, used on heavy trucks, trailers, or buses. The wheels on a tandem axle are typically mounted in pairs, with one pair per axle. This arrangement provides increased stability and load-bearing capacity compared to a single axle. Tandem axles are often used in combination with other suspension systems, such as air suspension or leaf springs, to optimize ride quality and handling. They can also be equipped with different types of brakes and tires to meet specific requirements.