Utah Air Brakes CDL Practice Test
Below are 25 exam-style questions for the Utah Air Brakes CDL knowledge test, modeled on the FMCSA-aligned content used by the Utah Driver License 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 5 psi per minute
- B 4 psi per minute
- C 2 psi per minute
- D 3 psi per minute
- A Pushrod travel within the legal limit for that brake type
- B No slack adjuster
- C Visible rust
- D Loose drum bolts
- A 0 to 10 psi
- B 20 to 45 psi
- C 90 to 100 psi
- D 60 to 80 psi
- A Show no signs of damage, leaks, or excessive wear
- B Be wrapped in tape
- C Be coiled tightly under the truck
- D Have at least 5 splices each
- A Running at high RPM
- B Off, with brakes released for the first part
- C In gear
- D Started and stopped repeatedly
- A Pump the brakes hard
- B Disconnect the trailer
- C Immediately stop on the side of the road
- D Continue driving — you still have normal brakes — and have the system checked at the next opportunity
- A They never need to be drained
- B They must be drained completely once a year
- C They drain themselves automatically in all trucks
- D They must be drained daily to remove water and oil
- A It will reduce engine power
- B It violates federal weight law
- C It can damage the rubber seals
- D It is bad luck
- A Disconnect the trailer
- B Pump the brake to fan down the pressure and verify the warning activates before pressure drops below 60 psi
- C Look at the dashboard light
- D Drain the wet tank only
- A At the bottom only
- B Once a year
- C In the middle of the descent
- D Before reaching the top, while still on level ground
- A A worn seat belt
- B Normal operation
- C A leak or restriction
- D A new compressor
- A The headlights
- B The horn
- C The service brakes for normal stops
- D The tail lights
- A The engine, by belts or directly geared
- B The transmission
- C The exhaust system
- D The electrical system
- A Heat from continuous brake use on long downgrades
- B Cold weather
- C Too much air pressure
- D Worn-out hoses
- A Bring the vehicle to a safe stop as soon as possible and find the cause
- B Increase engine RPM
- C Pump the brakes to keep pressure
- D Continue to the next exit
- A Both of the above
- B Neither of the above
- C Locking the wheels by braking too hard
- D Driving too fast for conditions
- A Perception + braking distance
- B Perception + reaction + brake-lag + braking distance
- C Reaction distance + braking distance
- D Reaction + braking + brake-lag distance
- A Air leaks could cause the brakes to release and let the vehicle roll
- B It is illegal
- C It will activate the spring brakes
- D It only works while the engine is running
- A Less than 30 seconds
- B 10 minutes
- C About 3 minutes in dual systems
- D It does not matter
- A Engine RPM
- B Brake pad wear
- C Coolant temperature
- D When the air compressor will pump air into the storage tanks
- A Hydraulic pressure
- B Engine vacuum
- C Electrical current
- D Air pressure
- A Test the brakes by lightly applying them at the top
- B Skip the brake test
- C Coast in neutral
- D Test the brakes at the bottom
- A Nothing happens
- B Trailer spring brakes apply automatically
- C Tractor brakes apply
- D Trailer service brakes apply
- A 10 psi
- B 5 psi
- C 2-3 psi
- D 1 psi
- A Setting the parking brake, releasing the service brake, and gently trying to move the vehicle
- B Pressing the service brake while parked
- C Doing nothing — the dashboard light is enough
- D Driving over a curb
Study tips for the Utah Air Brakes exam
The Air Brakes portion of the Utah CDL exam is graded out of the bank of questions the Utah Driver License Division draws from each year. While the exact bank is not published, every question is sourced from the Air Brakes chapter of the Utah 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 Utah 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 Air Brakes.
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 Utah Driver License 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 Air Brakes 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 Utah General Knowledge practice test before scheduling the real exam.
Next steps
Missed more than four questions? Re-read the Air Brakes study guide and the matching chapter in the official Utah 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 Utah Driver License Division office.
Already comfortable with this endorsement? Drill another: UT General Knowledge · UT Combination Vehicles · UT Hazardous Materials · UT Passenger · UT School Bus · UT Tank Vehicle · UT Doubles / Triples
New to the CDL process in Utah? Read How to apply for a CDL in Utah for the document checklist and step-by-step timeline.