MT CDL Air Brakes study plan
MT CDL Air Brakes · Give each week a clear focus.
8 weeks · About 6 hours per week
Air brake system components and their functions
Label every major component of a dual-circuit air brake system (compressor, governor, reservoirs, foot valve, relay valve, slack adjusters, chambers, spring brake chambers) on a blank diagram from memory
Explain in writing what each component does and what happens downstream when it fails
Trace the air path from compressor to brake chamber for both the primary and secondary circuits
Define the role of the governor cut-in and cut-out pressures and state typical values
Your checkpoint
A hand-drawn, fully labeled system diagram plus a one-page component-to-function table covering at least 12 components
Air brake system components and their functions & Dual air brake system and safety features (low pressure warning, spring brakes)
Describe how a dual-circuit system splits service braking so a single failure still leaves braking on one circuit
Explain the low pressure warning device: when it activates, what it signals, and the required threshold
Describe how spring brakes apply and release, including the role of air pressure holding them off
Identify the conditions that cause spring brakes to apply automatically
Your checkpoint
A written explanation (300+ words) of the dual-circuit layout and spring brake operation, checked against your notes for accuracy
Pre-trip inspection of the air brake system (leak tests, pressure buildup, warning devices)
List the steps of the pre-trip air brake inspection in correct order
State the static leak test procedure and acceptable pressure loss limits for a single vehicle
State the applied (service brake) leak test procedure and limits
Describe the compressor buildup test: from what pressure to what pressure, within what time
Describe how to test the low pressure warning and the spring brake (parking) function during pre-trip
Your checkpoint
A numbered pre-trip checklist you can perform and self-score, with pressure values and time limits written next to each step
Pre-trip inspection of the air brake system (leak tests, pressure buildup, warning devices) & Inspecting and using parking brakes and spring brakes
Perform the full pre-trip air brake inspection end to end without referring to notes
Demonstrate and explain the spring brake/parking brake test, including the tug test and the automatic application check
Explain out-of-service triggers found during inspection (e.g., excessive leakage, warning device failure, pushrod stroke out of adjustment)
Calculate and interpret pushrod stroke against the adjustment limit
Your checkpoint
A timed run-through of the inspection with a self-scored checklist and a written list of every out-of-service condition you can name
Normal driving with air brakes (braking technique, stopping distance, brake fade)
Explain proper braking technique on downgrades, including snubbing and controlled continuous braking
Describe how brake fade develops and how to recognize and respond to it
Explain how vehicle speed, weight, and road surface affect stopping distance
Describe the correct use of engine braking and gearing together with the service brakes
Your checkpoint
A one-page driving-technique summary plus 10 practice scenario answers (e.g., long downgrade, wet road, heavy load) written in exam-style wording
Emergency braking and brake failure procedures
List the immediate actions when brakes fail or pressure drops while driving
Explain the role of the emergency/parking spring brake as a backup stopping method
Describe how to use a runaway ramp and when to choose it
Distinguish between a partial loss (one circuit) and a total loss of braking and the response for each
Your checkpoint
A written emergency action sequence for at least five failure scenarios, each with ordered steps and a stated reason for each step
Air brake system maintenance, troubleshooting, and out-of-service criteria & Dual air brake system and safety features (low pressure warning, spring brakes)
Explain common air brake faults: compressor not building pressure, air dryer failure, leaking valves, frozen lines
Describe the troubleshooting sequence for low pressure buildup and for continuous pressure loss
State the maintenance checks a driver can legally and safely perform versus those requiring a mechanic
Reconfirm the low pressure warning and spring brake safety features and their inspection points
Your checkpoint
A troubleshooting flowchart for 'system will not build pressure' and 'pressure drops while driving', each with at least four diagnostic branches
Air brake system components and their functions & Dual air brake system and safety features (low pressure warning, spring brakes) & Pre-trip inspection of the air brake system (leak tests, pressure buildup, warning devices) & Normal driving with air brakes (braking technique, stopping distance, brake fade) & Emergency braking and brake failure procedures & Inspecting and using parking brakes and spring brakes & Air brake system maintenance, troubleshooting, and out-of-service criteria
Answer a full-length practice set covering all seven domains and score each domain separately
Re-study only the two weakest domains based on that score
Recite the key numeric values (leak limits, buildup time, warning thresholds, pushrod stroke limits) from memory
Re-perform the pre-trip inspection one final time under time pressure
Your checkpoint
A scored practice exam with a domain-by-domain breakdown and a one-page 'numbers and limits' cheat sheet written from memory
Milestones
Week 2: Can explain dual-circuit operation and spring brake function aloud, without notes, in under 3 minutes
Week 4: Completes the full pre-trip air brake inspection unaided and scores 90%+ on your own checklist, with correct leak and buildup values
Week 6: Can state the correct emergency response for brake failure and pressure loss without hesitation, and explain why spring brakes apply automatically
Week 8: Scores 85%+ overall on a full-length practice set with no domain below 75%, and reproduces all key numeric limits from memory