The general knowledge test is the first of several tests that you will have to complete in order to get your CDL. The questions cover general information about commercial vehicles, driving, and vehicle inspections. The test has a total of 50 questions, and requires at least 40 correct answers to pass.
You must have an Air brake endorsement on your driver's license to drive a vehicle equipped with an air brake system. This test will test your knowledge of the function, parts, and braking distance of air brakes. The test will consist of 25 questions, and at least 20 correct answers are needed to pass.
The combination endorsement allows you to drive a vehicle with a power unit and one trailer. This test will cover the "ins and outs" of operating articulated vehicles. The exam consists of 25 questions, and requires at least 20 correct to pass.
The Hazardous Material endorsement allows the driver to operate a vehicle containing items such as poisons, explosives, flammables, etc. You will also have to pass the TSA Hazardous Material Threat Assessment to get this endorsement. There are 30 questions, 24 correct required to pass.
The Tanker endorsement allows the driver to operate a vehicle weighing more than 26,000 pounds designed to transport any liquid or gaseous material within a tank that is permanently or temporarily attached to the vehicle. There are 20 questions, 16 correct required to pass.
The Doubles/Triples endorsement is required for drivers to pull 2 trailers (doubles) or 3 trailers (triples) connected to a single power unit. There are 20 questions on this test, and 16 correct answers are required to pass.
Bus drivers must have a commercial driver's license with a passenger endorsement in order to operate a vehicle which seats 16 or more, including the driver. There are 20 questions on this test, and 16 correct answers are required to pass.
School Bus Endorsement is required for any driver who operates a school bus. After the permit tests the training can be only completed by a local school district. There are 20 questions on this test, and 16 correct answers are required to pass.
The Pre-Trip exam is an oral exam where you are expected to check the vehicle parts to insure it is safe for road use. The amount of parts you need to check increase with the size of the vehicle, and by type of vehicle.