MO CDL Air Brakes Practice Test 4 2025

Getting a CDL that includes the air brake qualification is essential in Missouri. So many job opportunities are left on the table without the air brake qualification. To obtain it, you’ll need to pass both the Missouri DOR CDL Air Brakes Knowledge Test and the Skills Test in an air brake-equipped vehicle. This will remove the “L” code from your CDL, a restriction that would prohibit you from driving any commercial motor vehicle equipped with air brakes. Failing either test results in a one-day waiting period and a retest fee. You must score a minimum of 80% on the Knowledge Test in order to pass.

Because most Class A and Class B commercial vehicles use air brakes, including semi-trucks, heavy tractors, transit buses, motorcoaches, and large school buses, the “L” restriction definitely limits the jobs you can take. Our Missouri CDL Air Brakes Practice Tests are crafted to help you pass on the first attempt.

Our practice tests mirror the official DOR exam format. Test-takers may come across tricky wording, distractors, and double negatives in the official questions, creating confusion during the knowledge test. Our Missouri-specific practice tests introduce these situations ahead of time and are built using the latest Commercial Driver License Manual. Each practice question includes real-time feedback, clear AI-driven explanations, and proven learning techniques that improve retention and speed learning. Our practice materials feature an interactive CDL Manual as well as a Challenge Bank of questions that presents any missed questions again until you’ve answered them correctly. This thorough drill ensures you learn all the practice material before moving on. Try another practice test here: https://driving-tests.org/missouri/mo-cdl-air-brake-practice-test/.

Missouri drivers face conditions along I-44, I-70, I-55, and Route 60, and traffic congestion in St. Louis, Kansas City, Springfield, and Columbia that require precise stopping power and a skilled use of air brakes. The Show-Me State relies heavily on air brake-qualified drivers for industries including agriculture and livestock transport, manufacturing and distribution, logistics and freight, public transit and charter busing, and school district transportation (many full-size school buses require air brakes). Major employers, like Boeing, Ford Kansas City Assembly, General Motors suppliers, Hogan Transportation, Jefferson Lines, Metro Transit, Prime Inc., and YRC Freight, rely on air brake-qualified drivers.

You should also consider adding endorsements to your CDL, such as (N) Tanker, (H) Hazardous Materials, and (T) Doubles/Triples. We have Missouri Practice Tests to help you prepare for these knowledge tests as well: https://driving-tests.org/missouri/mo-cdl-hazmat-practice-test/. You might also check out our Combination Vehicles Practice Tests to prepare for the official combination exam, which is one of the major steps in obtaining a Class A License: https://driving-tests.org/missouri/mo-cdl-combination-test/.