Commercial Motor Vehicle (CMV) drivers must hold a Commercial Driver's License (CDL). To obtain a CDL, you must pass The CDL Test, which includes a general knowledge test, endorsement tests, and an air brakes test. Anyone who wishes to drive a vehicle equipped with air brakes must pass an Air Brakes test (heavy trucks or buses). If you fail the Air Brakes test, you will receive a restriction mark (restricted L) on your CDL, which indicates you will be unable to drive a CMV with air brakes.

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