Alabama CDL Combination Vehicles study plan

List the three parts of a combination vehicle and state the function of each

Explain how trailer weight shifts the center of gravity and affects stopping distance

Identify the two air brake systems on a tractor-trailer and describe what each supplies

Recite the correct braking sequence for a tractor-trailer from memory

Define tractor protection valve and state why it matters during a breakaway

Perform a full air brake system check on a real or simulated vehicle, in order, without prompting

Interpret the low-air warning threshold and explain the pressure at which the tractor protection valve should close

Describe the purpose of the trailer air supply and trailer hand valve controls

Identify the signs of air brake slack adjuster or pushrod problems during a walk-around

Explain how to test for air leaks at the couplings and what a passing result looks like

Sequence the coupling procedure from pre-positioning the tractor to the pull test

Explain why the fifth wheel jaws must be checked visually and by tug test

Sequence the uncoupling procedure including landing gear, air lines, and electrical cord

Identify the two most common causes of a dropped trailer and how to prevent each

Practice explaining each coupling step aloud as if instructing a new driver

Build a complete pre-trip inspection checklist for a combination vehicle covering tractor, trailer, and coupling

Locate and name each inspection point on the vehicle using correct terminology

Integrate the air brake check into the pre-trip sequence in the correct order

Explain what to look for at each point: tires, lights, hoses, fifth wheel, landing gear, and mud flaps

Identify which defects would place a vehicle out of service

Explain offtracking and predict how much the trailer will cut the corner in a given turn

Describe the correct lane position before, during, and after a right turn with a long trailer

Explain why a combination vehicle must swing wide and how to check for clearance on both sides

Describe proper following distance and the effect of speed on stopping distance

Explain how to change lanes safely with a trailer, including mirror use and blind spots

Describe the correct setup position for a straight-line backing maneuver

Explain the purpose of GOAL (Get Out And Look) and when it is required

Describe how to use mirrors and reference points to keep a trailer straight while backing

Explain the risks of backing a trailer into a blind side and how to minimize them

Describe safe parking practices on grades, including wheel chocks and parking brake use

Explain how speed, load height, and curve radius combine to create rollover risk

State the safe speed rule for curves and ramps and apply it to three example scenarios

Describe how to recognize and correct a trailer swing or jackknife early

Explain the effect of braking hard in a curve and why it increases rollover risk

List the conditions that require reducing speed below the posted limit

Review every domain using missed questions and weak spots from prior weeks

Rehearse the pre-trip inspection and air brake check back-to-back under time pressure

Re-explain coupling, uncoupling, and backing aloud without notes

Take a full-length practice exam and analyze every wrong answer

Build a final one-page cheat sheet of thresholds, sequences, and safety rules