Nevada Air Brakes CDL Practice Test
Below are 25 exam-style questions for the Nevada Air Brakes CDL knowledge test, modeled on the FMCSA-aligned content used by the Nevada Department 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 Perception + reaction + brake-lag + braking distance
- B Reaction + braking + brake-lag distance
- C Perception + braking distance
- D Reaction distance + braking distance
- A 2-3 psi
- B 1 psi
- C 5 psi
- D 10 psi
- A Increase engine RPM
- B Continue to the next exit
- C Pump the brakes to keep pressure
- D Bring the vehicle to a safe stop as soon as possible and find the cause
- A Tractor brakes apply
- B Trailer spring brakes apply automatically
- C Nothing happens
- D Trailer service brakes apply
- A When the air compressor will pump air into the storage tanks
- B Engine RPM
- C Brake pad wear
- D Coolant temperature
- A Set only the trailer parking brake
- B Leave both released
- C Set both tractor and trailer parking brakes
- D Set only the tractor parking brake
- A Running at high RPM
- B Started and stopped repeatedly
- C Off, with brakes released for the first part
- D In gear
- A It violates federal weight law
- B It is bad luck
- C It will reduce engine power
- D It can damage the rubber seals
- A The headlights
- B The tail lights
- C The horn
- D The service brakes for normal stops
- A It will activate the spring brakes
- B Air leaks could cause the brakes to release and let the vehicle roll
- C It only works while the engine is running
- D It is illegal
- A The transmission
- B The engine, by belts or directly geared
- C The electrical system
- D The exhaust system
- A Drain the wet tank only
- B Look at the dashboard light
- C Disconnect the trailer
- D Pump the brake to fan down the pressure and verify the warning activates before pressure drops below 60 psi
- A Caused by overuse
- B A normal feature
- C Required by federal law
- D A serious defect that can prevent backup braking
- A Pump rapidly
- B Stab the brakes
- C Press as hard as possible and hold
- D Release the brakes immediately
- A 10 minutes
- B About 3 minutes in dual systems
- C Less than 30 seconds
- D It does not matter
- A A leak or restriction
- B Normal operation
- C A worn seat belt
- D A new compressor
- A Wheel lockup during emergency braking
- B Engine overheating
- C Tire blowouts
- D Steering wander
- A The trailer hand valve releases
- B The engine stops
- C Nothing happens until you stop
- D Spring brakes apply automatically
- A Check tire pressures
- B Adjust the slack adjusters
- C Drain the wet tank
- D Pull forward and apply the foot brake to test for stopping
- A Pump the service brake five times
- B Drive immediately
- C Wait for full system pressure before moving
- D Drain the wet tank
- A The driver inflating the tank with a portable pump
- B The compressor pumping air back into the storage tanks
- C The vehicle's motion
- D The brake pedal
- A Electrical current
- B Engine vacuum
- C Hydraulic pressure
- D Air pressure
- A Air pressure should remain unchanged
- B Air pressure may drop slightly
- C Air pressure increases
- D The compressor cuts out
- A Be coated with oil
- B Have small cracks
- C Be glowing red after stops
- D Be free of cracks longer than half the width of the friction area
- 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
Study tips for the Nevada Air Brakes exam
The Air Brakes portion of the Nevada CDL exam is graded out of the bank of questions the Nevada Department of Motor Vehicles draws from each year. While the exact bank is not published, every question is sourced from the Air Brakes chapter of the Nevada 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 Nevada 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 Nevada Department 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 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 Nevada 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 Nevada 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 Nevada Department of Motor Vehicles office.
Already comfortable with this endorsement? Drill another: NV General Knowledge · NV Combination Vehicles · NV Hazardous Materials · NV Passenger · NV School Bus · NV Tank Vehicle · NV Doubles / Triples
New to the CDL process in Nevada? Read How to apply for a CDL in Nevada for the document checklist and step-by-step timeline.