Arizona Doubles / Triples CDL Practice Test
Below are 25 exam-style questions for the Arizona Doubles / Triples CDL knowledge test, modeled on the FMCSA-aligned content used by the Arizona Department of Transportation MVD. 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 Tractor cannot jackknife
- B Speed is reduced faster
- C Rear trailer can swing out and cause loss of control
- D Brakes work better
- A Set the parking brake or chock the wheels before disconnecting
- B Disconnect at high speed
- C Allow the dolly to roll
- D Skip the parking brake
- A Disconnect tractor first
- B Random order
- C No specific order
- D Reverse of coupling — disconnect rear trailer first, then dolly
- A Connect it to a random trailer
- B Disable the brakes
- C Leave it on a slope
- D Park it on level ground with the parking brake set or wheels chocked
- A Handling and braking are affected
- B Better fuel mileage
- C No effect
- D Better handling
- A A converter dolly
- B A tractor only
- C A trailer for transporting animals
- D A short trailer commonly used in doubles and triples
- A Skip the planning
- B Maintain speed
- C Turn sharply
- D Plan the turn carefully and use multiple lanes if necessary
- A Has the same rollover risk
- B Is less likely to roll
- C Is more likely to roll than the first
- D Cannot roll
- A Allow loose engagement
- B Allow chains to drag
- C Verify it is properly engaged and safety chains are attached
- D Skip the safety chains
- A The rear trailer swinging more than the tractor in turns or lane changes
- B A tire blowout
- C A driver punishing the truck
- D A loose load shifting
- A Two trailers behind one tractor
- B A bus with two sections
- C A trailer with two axles
- D Two tractors pulling one trailer
- A Skip the floor inspection
- B Inspect once a year
- C Look for damage that could affect cargo securement or trailer integrity
- D Allow damage
- A The tractor
- B The converter dolly
- C The rear trailer
- D The first trailer
- A Move cargo within the trailer
- B Replace the fifth wheel on the tractor
- C Test the brakes
- D Connect a semitrailer to another trailer to form a combination
- A Reduced visibility around the second trailer
- B Crosswind sensitivity
- C All of the above
- D Increased rollover risk in curves
- A Only the first trailer brakes
- B Only the rear trailer brakes
- C Tractor and trailer brakes
- D All trailer service brakes simultaneously
- A Couple without verifying
- B Allow the dolly to roll freely
- C Skip the air check
- D Verify the dolly's air tank has air pressure and lock the dolly's parking brake before backing under the second trailer
- A Only at the destination
- B Never; the dispatcher tests them
- C Before pulling away from the coupling site
- D Once a year
- A A combination with a second trailer that has a kingpin attached to the first trailer
- B A type of bus
- C A train carrying buses
- D A type of car carrier
- A Air lines from tractor to first trailer to dolly to second trailer
- B Mechanical brakes only
- C Air lines only on the tractor
- D No air-brake system
- A Brake within the curve
- B Slow down before the curve to reduce rollover risk and trailer swing
- C Maintain speed
- D Increase speed
- A In some states; restrictions vary
- B Only on Interstate 80
- C On all U.S. highways
- D In Canada only
- A Drive as if it were a single trailer
- B Be aware of the increased complexity of the equipment and operate accordingly
- C Use the trailer hand valve as a parking brake
- D Skip the pre-trip
- A The shoulder
- B The left lane
- C The right lane on multilane highways when possible
- D Any lane
- A Drive only at night
- B Avoid restricted roads and minimize sharp curves and steep grades
- C Take the shortest route regardless
- D Avoid freeways
Study tips for the Arizona Doubles / Triples exam
The Doubles / Triples portion of the Arizona CDL exam is graded out of the bank of questions the Arizona Department of Transportation MVD draws from each year. While the exact bank is not published, every question is sourced from the Doubles / Triples chapter of the Arizona 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 Arizona 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 Doubles / Triples.
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 Arizona Department of Transportation MVD 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 Doubles / Triples 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 Arizona General Knowledge practice test before scheduling the real exam.
Next steps
Missed more than four questions? Re-read the Doubles / Triples study guide and the matching chapter in the official Arizona 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 Arizona Department of Transportation MVD office.
Already comfortable with this endorsement? Drill another: AZ General Knowledge · AZ Air Brakes · AZ Combination Vehicles · AZ Hazardous Materials · AZ Passenger · AZ School Bus · AZ Tank Vehicle
New to the CDL process in Arizona? Read How to apply for a CDL in Arizona for the document checklist and step-by-step timeline.