Study Materials
Master every topic of the exam, in plain language.
Safe Driving: Speed, Space, and Seeing Hazards
More questions on the CDL General Knowledge test come from safe driving than from any other area, because almost every large-truck crash traces back to speed, following distance, or a hazard the driver saw too late. A loaded tractor-trailer can weigh twenty times what a car weighs, and that weight changes everything about how it stops, how it turns, and how much room it needs. This chapter covers stopping distance and how it grows with speed, the second-based following-distance rule, curves and mountain grades, driving at night and in rain, snow, and fog, skid recovery, railroad crossings and work zones, and the seeing and communicating habits that keep you out of trouble in the first place.
Vehicle Inspection: Pre-Trip, En-Route, and Post-Trip
Federal law makes the driver personally responsible for the condition of the vehicle, and no mechanic's signature transfers that duty away from you. Inspection questions on the General Knowledge test focus on what you must check, when you must check it, what the numeric limits are, and what paperwork the inspection generates. This chapter walks through the legal requirements for pre-trip, en-route, and post-trip inspections, the seven-step inspection method, the specific components and measurements examiners ask about, the air brake checks every air-brake driver must perform, and the defects that put a vehicle out of service.
Basic Control: Shifting, Backing, Turning, and Coupling
Controlling a heavy vehicle is a set of learned procedures rather than instincts carried over from driving a car. Shifting a manual transmission requires matching engine and road speed, backing requires giving up the natural habit of turning the wheel the direction you want to go, turning requires planning for a trailer that cuts the corner, and coupling requires a fixed sequence in which every step protects the one before it. This chapter covers shifting and engine speed ranges, safe backing and the GOAL habit, turning and off-tracking, coupling and uncoupling in order, parking, and the correct use of engine brakes and retarders.
Emergencies, Fires, Cargo, and Hazardous Materials
Emergencies happen fast, and the driver who has already decided what to do is the one who survives them. This chapter covers the emergency maneuvers a heavy-vehicle driver must know cold, including evasive steering, blowout response, off-road recovery, and brake failure, then moves to fire classes and the correct extinguisher for each, accident scene procedures, cargo weight and securement rules that keep a load where it belongs, and the basics of hazardous materials awareness and placarding that every CDL holder is expected to know even without an endorsement.
Hours of Service, Licensing, and Driver Fitness
The rules in this chapter are the ones that end careers when they are broken. Hours-of-service limits exist because fatigue impairs a driver much like alcohol does, the alcohol and drug rules for CDL holders are twice as strict as those for other drivers, and a short list of major offenses can disqualify a commercial license for a year or for life. This chapter covers the 11-hour, 14-hour, 30-minute, and 60/70-hour limits and the 34-hour restart, electronic logging, disqualifying offenses, alcohol and controlled substances, medical certification, distracted driving, and the fatigue and illness rules that require a driver to stop.
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