Maine Combination Vehicles CDL Practice Test
Below are 25 exam-style questions for the Maine Combination Vehicles CDL knowledge test, modeled on the FMCSA-aligned content used by the Maine Bureau 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 Hold the vehicle when parking
- B Apply trailer brakes momentarily
- C Both for parking and to prevent jackknife
- D Test the trailer brakes
- A Look at the locking jaws only
- B Tug the trailer with the trailer parking brakes set
- C Honk the horn
- D Listen for a click
- A Lane positioning at intersections
- B Cargo placement
- C The trailer following the same path as the tractor in a straight line
- D The fuel mileage
- A Cargo placement
- B Loose lug nuts only
- C Engine oil leaks
- D Cuts, abrasions, and worn seals
- A Loose or missing fifth-wheel mounting bolts
- B Cracks in the kingpin
- C Misalignment between tractor and trailer
- D All of the above
- A By pulling out the red trailer-air-supply valve
- B By setting the red trailer-air-supply valve
- C By the trailer hand valve
- D By pushing in the red trailer-air-supply valve
- A Sends air pressure to apply trailer service brakes
- B Sends supply air to the trailer reservoirs
- C Carries electrical power
- D Drains the trailer reservoir
- A Nothing will happen
- B The horn will sound
- C You will notice immediately because trailer brakes will not work properly
- D The trailer brakes will be locked on
- A Release the brakes to allow the trailer wheels to roll again, then steer
- B Accelerate
- C Apply the trailer hand valve harder
- D Disconnect the air supply
- A Maximum legal height
- B Whatever height it happens to be
- C A height where the tractor will lift the trailer slightly when backing under
- D A height that requires the tractor to drop down to fit
- A Have the dispatcher in the cab
- B GOAL — Get Out And Look — and walk around the trailer first
- C Back at full speed
- D Use only mirrors
- A Back as fast as practical
- B Back without using mirrors
- C Always back to the right
- D Back to the left whenever possible because you can see better
- A It is the standard procedure
- B It is fine if you are careful
- C It is illegal in some states
- D It can damage the cab and the trailer (cab corner crush)
- A No off-tracking
- B Off-tracking — the trailer wheels follow a tighter arc than the tractor
- C Wheel damage
- D Brake fade
- A Stops in the same distance
- B Stops faster than when loaded
- C May actually take longer to stop because brakes are designed for the loaded weight
- D Stops only with parking brake
- A Its center of gravity is high
- B It is shorter than a straight truck
- C Its tires are wider
- D It uses air brakes
- A Pump the brakes 10 times
- B Charge the trailer brakes by setting the trailer air supply control
- C Drain the wet tank
- D Drive away immediately
- A Trailer sway in crosswinds
- B Off-tracking on right turns
- C Reduced visibility along the trailer
- D All of the above
- A Cargo movement
- B Worn out tires
- C Driving too fast for conditions and/or too closely
- D Engine failure
- A Manual transmission shifters
- B Coupling devices for connecting tractor air lines to the trailer
- C Brake adjustment levers
- D Electrical connectors
- A Make the truck quieter
- B Only need attention every 5 years
- C Should be replaced when worn beyond manufacturer specs
- D Are normal until the lining is gone
- A Cross in a low gear without shifting
- B Stop on the tracks if traffic ahead slows
- C Shift in the middle of the track
- D Honk and accelerate
- A Triangular, green, marked SERVICE
- B Octagonal, red, marked TRAILER AIR SUPPLY
- C Round, blue, marked TRACTOR
- D Square, white, marked CHARGE
- A Keep the cab close to the curb and swing the front out so following cars cannot squeeze beside you on the right
- B Stop in the middle of the turn
- C Swing wide to the right first to avoid hitting the curb
- D Swing left then right
- A Be in the stowed (high) position when traveling
- B Be in the low position when traveling
- C Be removed
- D Be locked at half-height
Study tips for the Maine Combination Vehicles exam
The Combination Vehicles portion of the Maine CDL exam is graded out of the bank of questions the Maine Bureau 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 Maine 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 Maine 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 Maine Bureau 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 Maine 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 Maine 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 Maine Bureau of Motor Vehicles office.
Already comfortable with this endorsement? Drill another: ME General Knowledge · ME Air Brakes · ME Hazardous Materials · ME Passenger · ME School Bus · ME Tank Vehicle · ME Doubles / Triples
New to the CDL process in Maine? Read How to apply for a CDL in Maine for the document checklist and step-by-step timeline.