Alaska Combination Vehicles CDL Practice Test
Below are 25 exam-style questions for the Alaska Combination Vehicles CDL knowledge test, modeled on the FMCSA-aligned content used by the Alaska Division of Motor Vehicles. Try to answer each question on your own before reading the answer key directly under it. The questions and answer choices are shuffled deterministically per state and endorsement, so the order will stay the same on repeat visits — that lets you genuinely measure your improvement.
- A Sends air pressure to apply trailer service brakes
- B Drains the trailer reservoir
- C Sends supply air to the trailer reservoirs
- D Carries electrical power
- A Loose lug nuts only
- B Cuts, abrasions, and worn seals
- C Cargo placement
- D Engine oil leaks
- A Disconnect the air supply
- B Accelerate
- C Apply the trailer hand valve harder
- D Release the brakes to allow the trailer wheels to roll again, then steer
- A Lose engine power
- B Spin out
- C Roll over before sliding
- D Stop suddenly
- A Keep the cab close to the curb and swing the front out so following cars cannot squeeze beside you on the right
- B Swing left then right
- C Swing wide to the right first to avoid hitting the curb
- D Stop in the middle of the turn
- A The brakes are released gently
- B The drive wheels lock and the trailer pushes the tractor sideways
- C The trailer wheels lock briefly
- D You are driving slowly
- A Stop traffic by signaling left
- B Use the shoulder
- C Stay in the right lane and swing the front of the tractor wide enough to clear the curb without inviting cars to pass on the right
- D Turn from the left lane
- A Stopping distances are normal
- B Steering becomes easier
- C Stopping distances increase and the trailer can swing
- D No effect on safety
- A Disable the trailer parking brake
- B Check that the trailer is stable on its landing gear
- C Connect the lines back to the tractor
- D Move the tractor far away immediately without checking
- A Locked and the safety latch in place after coupling
- B Tied with rope
- C Removed before driving
- D Released and visible after coupling
- A Two car lengths
- B A vehicle length
- C No specific rule
- D One second per 10 feet of vehicle length below 40 mph, plus one extra second above 40 mph
- A Electrical power for trailer lights and ABS
- B Fuel
- C Hydraulic fluid
- D Air for the brakes
- A It is fine if you are careful
- B It can damage the cab and the trailer (cab corner crush)
- C It is the standard procedure
- D It is illegal in some states
- A Triangular, green, marked SERVICE
- B Round, blue, marked TRACTOR
- C Octagonal, red, marked TRAILER AIR SUPPLY
- D Square, white, marked CHARGE
- A Properly chocked
- B Empty
- C Loaded
- D Too high — it can damage the kingpin or skip over the fifth wheel
- A Performing the seven-step air-brake check before each trip
- B Listening to the brake light
- C Pressing the pedal once at startup
- D Asking a mechanic
- A Is used to convert a semitrailer into a full trailer for towing in combination
- B Replaces the fifth wheel on the tractor
- C Is part of the tractor
- D Is used only when triple-towing
- A Coupling with the trailer too high
- B Failure to grease
- C Backing too fast
- D All of the above
- A By the trailer hand valve
- B By pushing in the red trailer-air-supply valve
- C By pulling out the red trailer-air-supply valve
- D By setting the red trailer-air-supply valve
- A Driving too fast for conditions and/or too closely
- B Worn out tires
- C Engine failure
- D Cargo movement
- A Honk the horn
- B Listen for a click
- C Look at the locking jaws only
- D Tug the trailer with the trailer parking brakes set
- A Be in the stowed (high) position when traveling
- B Be locked at half-height
- C Be removed
- D Be in the low position when traveling
- A Steering wander only
- B Pulling, sticking, or unusual feel as you apply the brakes
- C Smoke from the cab
- D Engine knocking
- A Apply trailer brakes momentarily
- B Test the trailer brakes
- C Hold the vehicle when parking
- D Both for parking and to prevent jackknife
- A Honk the horn
- B Drain the air tanks
- C Lower the trailer landing gear and chock the trailer wheels
- D Disconnect the electrical line first
Study tips for the Alaska Combination Vehicles exam
The Combination Vehicles portion of the Alaska CDL exam is graded out of the bank of questions the Alaska Division of Motor Vehicles draws from each year. While the exact bank is not published, every question is sourced from the Combination Vehicles chapter of the Alaska CDL handbook, which itself is derived from the FMCSA Model Commercial Driver's License Manual. That means studying our practice tests, reading the corresponding handbook chapter, and re-reading the parts you got wrong is genuinely the most efficient route to a first-time pass.
Most successful applicants follow a simple cycle: take the practice test cold, write down every question you missed, open the matching chapter of the official Alaska handbook, re-read the section that contains the right answer, then re-take the practice test 24 to 48 hours later. The 24-hour delay matters — sleep is when your brain commits new information to long-term memory, and CDL knowledge questions reward that kind of consolidated learning rather than cramming.
Pay particular attention to questions that include qualifier words like always, never, only, primary, or most. CDL test writers love to flip the right answer with a single qualifier. When two answer choices look almost identical, pay attention to the verb (is it must, should, or may?) and to any numbers (14 days, 100 air miles, 8 hours, 70/8 split). On endorsement tests in particular, watch for trick framing where a true statement about a different endorsement is offered as the "correct" answer to a question that is actually about Combination Vehicles.
Test-day logistics matter too. Bring photo ID, your Social Security card or birth certificate, your medical examiner's certificate (DOT card), and proof of state residency if you haven't already submitted those documents. The Alaska Division of Motor Vehicles will not let you sit for the knowledge exam without your documentation, and most offices charge an additional fee for re-attempts. Arrive early — the wait at most CDL testing offices runs 30 to 60 minutes — and silence your phone before the exam begins.
Finally, keep your General Knowledge fundamentals sharp even when you're focused on the Combination Vehicles exam. Many states administer multiple knowledge tests in a single sitting, and questions on weight definitions (GVWR, GCWR, GAWR), stopping distance, and the pre-trip inspection routine show up across endorsements. If you're unsure on the basics, sit a fresh Alaska General Knowledge practice test before scheduling the real exam.
Next steps
Missed more than four questions? Re-read the Combination Vehicles study guide and the matching chapter in the official Alaska CDL handbook. Then come back and re-take the test. Once you can score 22 of 25 or higher on three runs in a row, you're in good shape to schedule the real exam at your local Alaska Division of Motor Vehicles office.
Already comfortable with this endorsement? Drill another: AK General Knowledge · AK Air Brakes · AK Hazardous Materials · AK Passenger · AK School Bus · AK Tank Vehicle · AK Doubles / Triples
New to the CDL process in Alaska? Read How to apply for a CDL in Alaska for the document checklist and step-by-step timeline.