Air Brakes Practice Test 4

Air Brakes isn't an endorsement — it's a restriction. Skip or fail it and you get an "L" restriction that bars you from driving any commercial vehicle with air brakes, which is most of them. The questions dig into how the system works, the dual air-brake setup, the parking and emergency brakes, and the daily air-brake checks you'll do on the road.

This free practice set runs 25 real exam-style questions with an instant, plain-English explanation after every answer. You'll work through them about ten at a time — answer the set, then continue to the next — and your running score saves automatically. You need 20/25 to pass the real Air Brakes exam.