CDL Greenlight

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CDL permit study guide: which tests you take

Every CDL permit starts with knowledge tests. Find the ones for the license and the endorsements you want, then study each with its guide.

By license class

Class A
Combination vehicles: a gross combination weight rating (GCWR) of 26,001 pounds or more, towing a vehicle rated (GVWR) over 10,000 pounds. Most are tractor-trailers.Tests:General knowledgeCombination vehicles
Class B
Heavy straight vehicles: one vehicle with a gross vehicle weight rating (GVWR) of 26,001 pounds or more, towing a vehicle rated 10,000 pounds or less. Straight trucks and large buses.Tests:General knowledge
Class C
Smaller vehicles, rated under 26,001 pounds (towing 10,000 pounds or less). Under the federal standard they need a CDL only when designed to carry 16 or more people including the driver, when placarded for hazardous materials, or when carrying a listed select agent or toxin. Add the passenger or hazmat test.Tests:General knowledge

In every class, take the air brakes test if your vehicle has air brakes, air over hydraulic included. Without it your license is restricted: no vehicle with air brakes. Air brakes

Endorsements

An endorsement adds its tests to those of your license class. A Class A driver hauling fuel in a tanker, for example, takes general knowledge, combination vehicles, air brakes if the truck has them, and tank vehicles. Some states require a CDL for more vehicles than the federal standard: check your state's manual.

T · Doubles and triples
Pulling double or triple trailers.Tests:Doubles and triples
N · Tank vehicle
Hauling a liquid or gas in tanks rated over 119 gallons each and 1,000 gallons or more in all.Tests:Tank vehicles
P · Passenger
Driving a vehicle designed to carry 16 or more people, including the driver.Tests:Passenger
S · School bus
Driving a school bus. Every bus driver also takes the passenger test.Tests:PassengerSchool bus
H · Hazardous materials
Hauling hazardous materials that need placards, or any amount of a listed select agent or toxin. You also pass a TSA background check.Tests:Hazardous materials
X · Hazmat and tank
A tank vehicle hauling hazardous materials that need placards: both tests.Tests:Hazardous materialsTank vehicles

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