This testing sequence consists of seven different procedures: structural shakedown, structural distortion, static and dynamic towing, jacking, hoisting, and structural durability. In one test of a bus's structural integrity, a shakedown test is performed. First, the bus frame is isolated from the suspension system to prevent the frame from moving prior to loading. Ballast equal to two-and-a-half times the maximum passenger capacity is loaded onto the bus. With the bus loaded, deflection is measured at strategic positions under the bus to determine the settling or movement of the frame. Later, the process of loading is reversed, and measurements recorded again when the bus is unloaded to determine if any permanent deformation has occurred. This shakedown sequence is performed a total of three times.

Structural distortion testing recreates the action of a bus traveling over a curb or through a pothole. The objective is to observe the operation of the bus subsystems when the bus is placed in a longitudinal twist.  With the bus loaded to gross vehicle weight, each wheel is raised and lowered individually during the test procedure. Then a technician sprays water over the length of the bus. Another technician inside the bus inspects the doors and windows for leaks or cracks.

At PTI's Bus Research and Testing Facility, a special vehicle durability test track was designed to simulate the types of pavement conditions that a bus would experience during routine operations. Buses are subjected to an accelerated durability test on this test track that is intended to approximate 25% of the service life of the bus. The test is conducted under  three different loading conditions: gross vehicle weight, seated load weight, and curb weight. During testing, all bus subsystems (the doors, lights, wheel chair lifts, and other equipment) are used in their normal operating modes. Once a week the test bus is washed down and thoroughly inspected for any signs of failure.