Trucks usually have large wheels, a low center of gravity, and low ground pressure. It is a common misconception that a truck has large axles, and long wheelbase and frame to accommodate these large tires. In fact, the main purpose of the chassis is to distribute the road load evenly to the four wheels. A well-designed Truck Accessories chassis has sufficient torsional rigidity to resist flexing. The chassis consists of a pair of beam subframes mounted longitudinally on top and bottom of the frame rails, which supports the axles. Each axle assembly includes a spindle, bearings, halfshafts, and steering knuckles. The front wheels have tie rods to connect to the frame while the rear wheels have universal joints to provide the same function. The front and rear suspension components are mounted on the frame rails, with the front suspension mounting points higher than the rear ones. This difference in height is necessary to clear the drive shaft and torque tube.