How to Check Tractor & Trailer Brakes (CDL Air Brake Test Tutorial) 📘 YouTube Description: Learn the correct and simplest way to check your tractor brake, trailer brake, and service brake during your CDL Air Brake Test. 🚛💨 In this step-by-step walkthrough, we cover: ✔️ How to test the tractor brake ✔️ How to test the trailer brake ✔️ What vibration/tug you should feel ✔️ What your examiner is looking for ✔️ Common mistakes to avoid Whether you're getting ready for your CDL exam or brushing up