Nebraska CDL Combination Vehicles study plan

Define combination vehicle terminology from the Nebraska CDL manual: tractor, trailer, fifth wheel, kingpin, landing gear, glad hands, and converter dolly.

Explain why combination vehicles require more stopping distance and wider turns than single-unit trucks, citing weight transfer and off-tracking.

List the three coupling systems on a tractor-trailer (air lines, electrical cord, fifth wheel) and state the consequence of failing to secure each.

Identify the inspection items a driver must check before moving a coupled combination vehicle.

Describe the step-by-step procedure for coupling a tractor to a trailer, including the pre-coupling inspection and the tug test.

Describe the step-by-step procedure for uncoupling, including landing gear placement and disconnecting air lines in the correct order.

Explain the purpose of the trailer hand valve and the tractor protection valve, and when each is used.

Identify the common coupling errors that cause dropped trailers and state how the tug test catches them.

Explain how air pressure builds and is distributed through the tractor and trailer brake systems, including the role of the supply line and service line.

Describe the low-air warning and emergency spring-brake activation sequence, and state the pressure at which each occurs.

Perform a written leak-down and pressure-loss test walkthrough, recording target pressures and acceptable loss rates.

Explain how a trailer air supply valve (red knob) and parking brake valve (yellow knob) interact during a brake check.

Explain the effect of trailer length, load placement, and axle weight on off-tracking and turn radius.

Describe proper lane positioning and turning technique for right and left turns with a 53-foot trailer.

Explain how to check clearance and mirrors during a turn and when to swing wide without crossing into an unsafe lane.

Describe how to back a combination vehicle, including the use of GOAL (get out and look) and a spotter.

Describe how to control speed on downgrades using engine braking, gearing, and service brakes, and explain why continuous brake application causes fade.

Explain the causes and warning signs of trailer swing, jackknifing, and rearward amplification, and state the corrective action for each.

Describe the procedure for recovering from a skid in a combination vehicle, including steering and brake inputs.

Explain how to handle a tire blowout, brake failure, and loss of trailer air supply at highway speed.

Explain the inspection requirements for combination vehicles, including the pre-trip, en-route, and post-trip inspection items.

Describe how to inspect the fifth wheel, kingpin, landing gear, mud flaps, and rear impact guard.

Explain cargo securement requirements for flatbed and van trailers, including tie-down count and working load limits.

Describe how to check coupling security after an en-route stop.

Review the Nebraska CDL combination vehicle knowledge test format and identify the passing score and question count.

Complete at least two full-length practice tests and record scores by topic to find weak areas.

Re-study the two weakest topics and write a short explanation of each in your own words.

Practice the pre-trip inspection walkthrough aloud within the time limit.

Complete a final full-length practice test and score at or above the passing threshold.

Recite the coupling and uncoupling checklists from memory without notes.

Review all missed questions from weeks 1-7 and confirm each is now understood.

Confirm test-day logistics, including required documents and appointment time.