All your missed questions are saved
automatically for extra practice.
It's a practice test that's automatically made up of all your missed questions. Once you finish this test, you’ll be able to revisit your Challenge Bank™ to practice and sharpen your skills.
View All PlansAdding difficult questions to Challenge Bank™ is an exclusive Premium feature. Unlock access to 650+ exam-like questions, a Pass Guarantee, personalized study plans, and more.
View All PlansReady for something a little different? This Iowa CDL Air Brakes Marathon is a massive practice test that contains a mixture of all 183 questions that we have available for this IA endorsement. If you give an incorrect 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”. Give it your best shot!
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Last verified for accuracy: November 2025 (reviewed weekly)
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