Indiana Combination Vehicles CDL Practice Test
Below are 25 exam-style questions for the Indiana Combination Vehicles CDL knowledge test, modeled on the FMCSA-aligned content used by the Indiana Bureau 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 Disconnect the electrical line first
- B Honk the horn
- C Drain the air tanks
- D Lower the trailer landing gear and chock the trailer wheels
- A Engine damage
- B Tire wear only
- C The trailer to come uncoupled
- D Rust on the cab
- A Every 3 hours
- B Before, during, and after coupling
- C Only at the start of the day
- D Only at the destination
- A Its center of gravity is high
- B It is shorter than a straight truck
- C It uses air brakes
- D Its tires are wider
- A Lower the landing gear all the way until firmly on the ground, then a few extra cranks
- B Use blocks instead
- C Raise the gear partway
- D Leave the gear up
- A Tied with rope
- B Locked and the safety latch in place after coupling
- C Removed before driving
- D Released and visible after coupling
- A Engine oil leaks
- B Cuts, abrasions, and worn seals
- C Loose lug nuts only
- D Cargo placement
- A Pulling, sticking, or unusual feel as you apply the brakes
- B Smoke from the cab
- C Steering wander only
- D Engine knocking
- A Connect any line first; order doesn't matter
- B Connect only air; electrical is optional
- C Connect air emergency line first, then service line, then electrical (or per company policy) — verify with brake check
- D Connect electrical first, then air
- A Sends supply air to the trailer reservoirs and controls the trailer emergency brakes
- B Carries electrical signals
- C Drains the wet tank
- D Operates the parking brake only
- A Swing wide to the right first to avoid hitting the curb
- B Keep the cab close to the curb and swing the front out so following cars cannot squeeze beside you on the right
- C Stop in the middle of the turn
- D Swing left then right
- A Are caused by low fuel
- B Need a mechanic to find
- C Can be detected during pre-trip inspection by visual and pressure checks
- D Show up only at high speed
- A The trailer wheels follow a tighter arc than the tractor wheels in a turn
- B Loss of traction
- C Sliding sideways
- D Driving off the road
- A It is fine if you are careful
- B It is illegal in some states
- C It can damage the cab and the trailer (cab corner crush)
- D It is the standard procedure
- A Both for parking and to prevent jackknife
- B Hold the vehicle when parking
- C Test the trailer brakes
- D Apply trailer brakes momentarily
- A A wheel bearing fails
- B The tractor brakes lock up
- C The fifth wheel breaks
- D The trailer brakes lock up
- A Always back to the right
- B Back to the left whenever possible because you can see better
- C Back as fast as practical
- D Back without using mirrors
- A Connect the lines back to the tractor
- B Disable the trailer parking brake
- C Check that the trailer is stable on its landing gear
- D Move the tractor far away immediately without checking
- A Stop traffic by signaling left
- B Turn from the left lane
- C Stay in the right lane and swing the front of the tractor wide enough to clear the curb without inviting cars to pass on the right
- D Use the shoulder
- A The trailer wheels lock briefly
- B The brakes are released gently
- C You are driving slowly
- D The drive wheels lock and the trailer pushes the tractor sideways
- A Listening to the brake light
- B Pressing the pedal once at startup
- C Performing the seven-step air-brake check before each trip
- D Asking a mechanic
- A Failure to grease
- B Coupling with the trailer too high
- C Backing too fast
- D All of the above
- A Steering becomes easier
- B No effect on safety
- C Stopping distances increase and the trailer can swing
- D Stopping distances are normal
- A The tractor parking brake fails
- B The trailer is too heavy
- C The drive wheels lose traction and the tractor begins to slide
- D The fifth wheel disengages
- A Driver fatigue
- B Engine wear
- C Cargo placement
- D Air leakage in the supply line, low pressure, or a brake-balance issue
Study tips for the Indiana Combination Vehicles exam
The Combination Vehicles portion of the Indiana CDL exam is graded out of the bank of questions the Indiana Bureau of Motor Vehicles draws from each year. While the exact bank is not published, every question is sourced from the Combination Vehicles chapter of the Indiana 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 Indiana 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 Indiana Bureau 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 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 Indiana 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 Indiana 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 Indiana Bureau of Motor Vehicles office.
Already comfortable with this endorsement? Drill another: IN General Knowledge · IN Air Brakes · IN Hazardous Materials · IN Passenger · IN School Bus · IN Tank Vehicle · IN Doubles / Triples
New to the CDL process in Indiana? Read How to apply for a CDL in Indiana for the document checklist and step-by-step timeline.