North Dakota Combination Vehicles CDL Practice Test
Below are 25 exam-style questions for the North Dakota Combination Vehicles CDL knowledge test, modeled on the FMCSA-aligned content used by the North Dakota Department of Transportation. 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 Coupling with the trailer too high
- B All of the above
- C Failure to grease
- D Backing too fast
- A Properly chocked
- B Loaded
- C Empty
- D Too high — it can damage the kingpin or skip over the fifth wheel
- A Air for the brakes
- B Electrical power for trailer lights and ABS
- C Hydraulic fluid
- D Fuel
- A Only at the start of the day
- B Only at the destination
- C Every 3 hours
- D Before, during, and after coupling
- A Last
- B Loaded last
- C Either position is fine
- D First (closest to the tractor)
- A Stop suddenly
- B Roll over before sliding
- C Lose engine power
- D Spin out
- A Back to the left whenever possible because you can see better
- B Back as fast as practical
- C Back without using mirrors
- D Always back to the right
- A The fifth wheel disengages
- B The tractor parking brake fails
- C The trailer is too heavy
- D The drive wheels lose traction and the tractor begins to slide
- A The fuel mileage
- B Cargo placement
- C Lane positioning at intersections
- D The trailer following the same path as the tractor in a straight line
- A One second per 10 feet of vehicle length below 40 mph, plus one extra second above 40 mph
- B No specific rule
- C Two car lengths
- D A vehicle length
- A Stop on the tracks if traffic ahead slows
- B Cross in a low gear without shifting
- C Shift in the middle of the track
- D Honk and accelerate
- A Its tires are wider
- B Its center of gravity is high
- C It is shorter than a straight truck
- D It uses air brakes
- 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 Loose lug nuts only
- B Engine oil leaks
- C Cargo placement
- D Cuts, abrasions, and worn seals
- A You are driving slowly
- B The drive wheels lock and the trailer pushes the tractor sideways
- C The brakes are released gently
- D The trailer wheels lock briefly
- A Brake balance is irrelevant
- B Trailer wheels lock more often than drive wheels in panic stops
- C Drive wheels never lock
- D ABS prevents jackknife in all cases
- A Set only the tractor parking brake
- B Set both tractor and trailer parking brakes
- C Use the trailer hand valve
- D Leave the engine running with the brakes off
- A Large trailer angle changes; small inputs are key
- B Small trailer movement
- C Loss of brake pressure
- D No effect
- A Cargo movement
- B Worn out tires
- C Engine failure
- D Driving too fast for conditions and/or too closely
- A Tug the trailer with the trailer parking brakes set
- B Look at the locking jaws only
- C Honk the horn
- D Listen for a click
- A Be open
- B Be closed around the shank of the kingpin (not on the head)
- C Be missing
- D Be loose
- A Connect any line first; order doesn't matter
- B Connect air emergency line first, then service line, then electrical (or per company policy) — verify with brake check
- C Connect electrical first, then air
- D Connect only air; electrical is optional
- A Engine knocking
- B Smoke from the cab
- C Pulling, sticking, or unusual feel as you apply the brakes
- D Steering wander only
- A Pump the brakes 10 times
- B Charge the trailer brakes by setting the trailer air supply control
- C Drive away immediately
- D Drain the wet tank
- A The fifth wheel breaks
- B The trailer brakes lock up
- C The tractor brakes lock up
- D A wheel bearing fails
Study tips for the North Dakota Combination Vehicles exam
The Combination Vehicles portion of the North Dakota CDL exam is graded out of the bank of questions the North Dakota Department of Transportation draws from each year. While the exact bank is not published, every question is sourced from the Combination Vehicles chapter of the North Dakota 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 North Dakota 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 North Dakota Department of Transportation 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 North Dakota 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 North Dakota 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 North Dakota Department of Transportation office.
Already comfortable with this endorsement? Drill another: ND General Knowledge · ND Air Brakes · ND Hazardous Materials · ND Passenger · ND School Bus · ND Tank Vehicle · ND Doubles / Triples
New to the CDL process in North Dakota? Read How to apply for a CDL in North Dakota for the document checklist and step-by-step timeline.