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CO CDL Air Brakes Marathon

Need one final boost? This Colorado CDL Air Brakes Marathon is a new study tool that contains a mixture of all 183 questions that we have available for this CO endorsement. If you select a wrong answer, we’ll remember that question and will display it to you again at the end of the exam until you’ve answered that question correctly. In other words, the Marathon will cycle through your missed questions until you answer each one correctly. You must make a 100% to pass. We suggest you attempt this one after you have practiced the state’s “regular” tests, but before the “Exam”. Good luck!

Perfect for

  • First-time CO CDL and CLP applicants
  • CDL holders adding endorsements
  • CO CDL renewal applicants
CO commercial driver's license

What to expect on the actual exam

How many questions25
How many correct answers to pass20
Passing score80%
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