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View All PlansTo legally operate double or triple trailer combinations in Colorado, you must pass the Doubles/Triples Knowledge Test, which adds the T Endorsement to your Class A CDL. Our Free Colorado CDL Doubles/Triples Practice Tests are scientifically crafted to mimic the official test format and maximize first-time success. These tests offer real-time feedback, built-in hints, and AI learning tools to help you master concepts faster and retain information longer than traditional study methods.
The official endorsement exam consists of 20 multiple-choice questions, at least 16 of which you must answer correctly (80%) to pass. If you fail, the Colorado Division of Motor Vehicles (DMV) requires a minimum one-business-day waiting period before retesting, and a fee applies after three failed attempts. This is why our practice tests are important: they ensure you pass on your first attempt.
Questions are based on the most recent Colorado CDL Manual. Topics covered include safe driving techniques like smooth, steady steering to avoid rollovers. Additionally, proper coupling and uncoupling procedures, preventing jackknifing and rollovers, using the correct braking techniques for longer combination vehicles, following distances, and thorough inspection checklists for all trailers are covered.
Adding a T Endorsement in Colorado enhances your CDL and opens doors to higher-paying jobs. With major trucking roadways such as I-25, I-70, and I-76 and logistics hubs in Denver, Colorado Springs, Aurora, and Grand Junction, CDL drivers with T endorsements are in high demand. Additionally, major organizations like Swift Transportation, XPO, and FedEx Freight constantly recruit drivers certified for doubles and triples for their transit needs.
Colorado also offers endorsements for Tanker (N), Hazardous Materials (H), the X Combo Endorsement, Passenger (P) vehicles, and School Buses (S). Each of these endorsements requires its own separate knowledge test, and we offer Colorado-specific practice tests to help you pass them all on your first attempt!
Most double/triple trailer combinations use air brakes, so you’ll also need to pass the Air Brakes Knowledge Test to remove the “L” or “Z” restriction from your CDL. And you guessed it: we have Colorado Air Brakes practice tests, too!
This is Practice Test Two of our Colorado CDL Doubles/Triples series. Be sure to check out Practice Test One, along with our complete set of endorsement and air brake practice tests designed to reflect Colorado DMV requirements.
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