New Mexico Doubles / Triples CDL Practice Test
Below are 25 exam-style questions for the New Mexico Doubles / Triples CDL knowledge test, modeled on the FMCSA-aligned content used by the New Mexico Motor Vehicle Division. 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 Restrictions apply only to hazmat
- B Federal and state rules vary; T endorsement does not override route restrictions
- C T endorsement allows triples everywhere
- D There are no restrictions
- A A bus with two sections
- B A trailer with two axles
- C Two trailers behind one tractor
- D Two tractors pulling one trailer
- A Use the left lane
- B Off-tracking is less than a single trailer
- C No off-tracking occurs
- D Off-tracking is more pronounced; swing wider than for a single trailer
- A Air lines, electrical lines, and connection points
- B Fuel tanks
- C Engines
- D Drivers
- A Dolly air-tank pressure
- B Glad hands and seals at every connection
- C Pintle hooks and safety chains
- D All of the above
- A A converter dolly
- B A short trailer commonly used in doubles and triples
- C A tractor only
- D A trailer for transporting animals
- A Connect it to a random trailer
- B Park it on level ground with the parking brake set or wheels chocked
- C Leave it on a slope
- D Disable the brakes
- A Trailers first, then tractor
- B Drop first trailer, hook converter dolly to first trailer, back tractor to second trailer, etc.
- C Random order
- D Tractor to second trailer first
- A Trailer length only
- B No specific length
- C Tractor length only
- D Total combination length when turning, parking, and changing lanes
- A No air-brake system
- B Mechanical brakes only
- C Air lines from tractor to first trailer to dolly to second trailer
- D Air lines only on the tractor
- A Allow damage
- B Skip the floor inspection
- C Inspect once a year
- D Look for damage that could affect cargo securement or trailer integrity
- A Steer sharply
- B Reduce speed gradually and avoid sudden steering inputs
- C Brake hard
- D Accelerate
- A A tire blowout
- B The rear trailer swinging more than the tractor in turns or lane changes
- C A driver punishing the truck
- D A loose load shifting
- A Only the rear trailer brakes
- B Tractor and trailer brakes
- C All trailer service brakes simultaneously
- D Only the first trailer brakes
- A Cut between cars
- B Skip the signal
- C Plan the change well in advance, signal early, and change when there is ample space
- D Change quickly to fit in
- A In Canada only
- B In some states; restrictions vary
- C On all U.S. highways
- D Only on Interstate 80
- A Includes a pintle hook on the front and a fifth wheel on the back
- B Is the same as a tractor fifth wheel
- C Is electrical only
- D Is a single hook
- A Signal early and change smoothly to minimize swing
- B Change quickly without signaling
- C Change at high speed
- D Change in heavy traffic
- A Use the trailer hand valve
- B Set only the tractor parking brake
- C Set parking brakes on the tractor and on the trailers
- D Leave brakes off
- A Connect a semitrailer to another trailer to form a combination
- B Move cargo within the trailer
- C Test the brakes
- D Replace the fifth wheel on the tractor
- A Couple without verifying
- B Skip the air check
- C Verify the dolly's air tank has air pressure and lock the dolly's parking brake before backing under the second trailer
- D Allow the dolly to roll freely
- A Use the spare
- B Continue with damaged tires
- C Ignore the damage
- D Replace before operating
- A The second trailer's emergency brakes apply automatically
- B The tractor brakes apply
- C Nothing happens
- D The first trailer accelerates
- A Can maintain normal speed
- B Should brake hard
- C Should change lanes frequently
- D Should be driven slowly with extra following distance
- A All trailers should brake together if the system is functioning correctly
- B Only the rear trailer brakes
- C Brakes are uneven
- D Only the first trailer brakes
Study tips for the New Mexico Doubles / Triples exam
The Doubles / Triples portion of the New Mexico CDL exam is graded out of the bank of questions the New Mexico Motor Vehicle Division draws from each year. While the exact bank is not published, every question is sourced from the Doubles / Triples chapter of the New Mexico 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 New Mexico 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 New Mexico Motor Vehicle Division 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 New Mexico 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 New Mexico 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 New Mexico Motor Vehicle Division office.
Already comfortable with this endorsement? Drill another: NM General Knowledge · NM Air Brakes · NM Combination Vehicles · NM Hazardous Materials · NM Passenger · NM School Bus · NM Tank Vehicle
New to the CDL process in New Mexico? Read How to apply for a CDL in New Mexico for the document checklist and step-by-step timeline.