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Indiana General Knowledge CDL Practice Test

Below are 25 exam-style questions for the Indiana General Knowledge 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.

Heads up: this is a study tool, not a graded exam. Cover the answer with your hand or a sheet of paper for an honest practice run, then re-read the explanations for any questions you missed. Aim for 22 out of 25 or better, three times in a row, before scheduling the real exam.
Question 1 of 25
Which of the following is a sign of fatigue?
  • A Frequent yawning
  • B All of the above
  • C Drifting in your lane
  • D Trouble remembering the last few miles
Correct answer: B
All three are classic fatigue indicators in the FMCSA model. Cold air, music, and caffeine are not effective fixes — only sleep is.
Question 2 of 25
On a long downgrade, why is it dangerous to use the brakes too much?
  • A It wastes brake pads
  • B It triggers the ABS warning light
  • C It cools the brakes too much
  • D Brake fade can leave you with reduced or no braking power
Correct answer: D
Heat from continuous braking causes the friction surfaces to lose their grip. Use a low gear and brief, moderate brake applications.
Question 3 of 25
Cargo that hangs more than 4 feet beyond the back of the vehicle must be marked with:
  • A Yellow tape only
  • B A green flag
  • C Nothing — federal rules do not require marking
  • D A red flag (or red light at night) at the extreme rear
Correct answer: D
Federal rules require a red flag during the day and red lights at night for projecting cargo beyond 4 feet.
Question 4 of 25
Which is true about brake lining wear and adjustment?
  • A Brakes self-adjust forever
  • B Drum brakes never need adjustment
  • C Brake adjustment is the dispatcher's responsibility
  • D Slack adjusters need periodic checking; pushrod travel beyond limits is out-of-service
Correct answer: D
Slack adjusters can fail, and pushrod travel must be within limits. Drivers check; adjustment itself is a maintenance task for qualified personnel.
Question 5 of 25
The two main reasons why a driver's feet are kept off the brakes when not actively braking are:
  • A To save brake pads and reduce drag
  • B To save fuel and improve mileage
  • C So the brake lights don't mislead following drivers and so the brakes don't overheat
  • D To rest the right leg
Correct answer: C
Riding the brake lights confuses drivers behind you and gradually heats the friction surfaces, both of which are safety problems.
Question 6 of 25
When checking the engine compartment, you should make sure that:
  • A Power steering fluid is at the proper level
  • B Engine oil level is safe to operate
  • C All of the above
  • D Coolant level is above LOW and the cap is secure
Correct answer: C
A proper engine-compartment check covers oil, coolant, power steering fluid, windshield washer fluid, hoses, belts, and electrical wiring. Skipping any one of them defeats the purpose of the inspection.
Question 7 of 25
When approaching a curve, you should:
  • A Downshift in the curve
  • B Stay at the same speed
  • C Brake while in the curve
  • D Slow down before entering and accelerate gently through it
Correct answer: D
Speed should already be set before the curve. Braking or downshifting in a curve can upset the vehicle's balance.
Question 8 of 25
When approaching a steep downgrade, the basic safe-driving rule is:
  • A Coast in neutral
  • B Use the parking brake intermittently
  • C Stay in high gear
  • D Select a lower gear before starting down
Correct answer: D
Get into a low gear before the descent so the engine helps hold the vehicle back.
Question 9 of 25
When should you use four-way flashers?
  • A Only on the highway
  • B When you are stopped or moving slowly enough to be a hazard
  • C Only at night
  • D Whenever you feel like it
Correct answer: B
Four-ways are for vehicles stopped on or near the road or moving so slowly that they are a hazard.
Question 10 of 25
How does ABS help in an emergency stop?
  • A It increases brake pressure automatically
  • B It always stops the vehicle in a shorter distance
  • C It applies the parking brake
  • D It prevents wheel lockup so the driver can keep steering
Correct answer: D
ABS keeps the wheels rolling so steering control is preserved. It is not a shorter-distance device.
Question 11 of 25
Skids are most often caused by:
  • A Properly working brakes
  • B Manual transmissions
  • C Old tires
  • D Driving too fast for conditions
Correct answer: D
The dominant cause of skids identified by the FMCSA is driving too fast for the road or weather. Sudden steering, hard braking, or hard acceleration usually triggers them.
Question 12 of 25
The most important hand position on the steering wheel is:
  • A 10 and 2 (or 9 and 3)
  • B One hand at 12
  • C 12 and 6
  • D Both hands at the bottom
Correct answer: A
A balanced grip at 10-and-2 or 9-and-3 gives the most control. One-handed and bottom-of-wheel positions reduce reaction time.
Question 13 of 25
When backing a heavy vehicle, you should:
  • A Back fast to get it over with
  • B Use a helper and walk around the vehicle first
  • C Back to the right whenever possible
  • D Back without using mirrors so you can watch out the window
Correct answer: B
Always GOAL — Get Out And Look — and use a helper. Backing to the left when possible is preferred because you can see better, not to the right.
Question 14 of 25
You are driving on a two-lane road and you see a driver about to pull out from a side road. You should:
  • A Move to the right lane
  • B Honk and accelerate
  • C Maintain speed
  • D Cover the brake and slow down
Correct answer: D
Anticipate the worst-case behavior. Cover the brake — keeping your foot just over it — so you can react if they pull out.
Question 15 of 25
A Class C CDL is required to drive:
  • A Class A combinations only
  • B Tractor-trailers under 26,001 lbs GCWR
  • C Any vehicle over 26,001 lbs
  • D Vehicles designed to carry 16+ passengers including the driver, or that require hazmat placards
Correct answer: D
Class C covers vehicles that don't meet Class A or B but are designed to carry 16 or more passengers (including the driver) or carry placarded amounts of hazardous materials.
Question 16 of 25
Which is true about communicating in heavy traffic?
  • A Tap the horn lightly or flash lights to signal your presence
  • B Honk loudly to warn other drivers
  • C Never communicate; just drive
  • D Make eye contact only when stopped
Correct answer: A
A light tap of the horn or a brief headlight flash communicates your presence without startling others. A loud, prolonged horn can provoke aggressive responses.
Question 17 of 25
What does GVWR stand for?
  • A Government Vehicle Weight Regulation
  • B Gross Vehicle Weight Rating
  • C Gross Vehicle Width Rating
  • D General Vehicle Weight Reading
Correct answer: B
GVWR is the maximum weight the manufacturer says a single vehicle can safely weigh, including itself plus its load.
Question 18 of 25
Which is true about driving in rain?
  • A It is safe to drive at the posted speed limit
  • B Tire chains are required by federal law
  • C High beams improve visibility in heavy rain
  • D Roads are most slippery just after rain begins, when water mixes with road oil
Correct answer: D
The first few minutes of rain mix with oil and grime on the road and create the slipperiest conditions. Slow down and increase following distance.
Question 19 of 25
Which of the following is a valid reason to refuse a load?
  • A It would make you exceed federal hours-of-service rules
  • B It would push your weight over legal limits
  • C The cargo is not properly secured or placarded
  • D All of the above
Correct answer: D
A driver is required by federal law to refuse loads that violate HOS, weight, or hazmat rules. The driver, not the dispatcher, is liable.
Question 20 of 25
Acceleration must be smooth and gradual to avoid:
  • A Annoying passengers
  • B Wasting fuel only
  • C Engine damage
  • D Powertrain wear and possible loss of control on slippery surfaces
Correct answer: D
Quick throttle inputs on slick surfaces can spin the drive wheels and cause a tractor jackknife. Smooth acceleration avoids this and reduces wear.
Question 21 of 25
A driver must report any accident involving a CMV to the carrier within:
  • A 24 hours
  • B 7 days
  • C A reasonable time, before going off duty
  • D 1 hour
Correct answer: C
FMCSA rules require notification of the motor carrier in a reasonable time — most policies treat that as before going off duty.
Question 22 of 25
A "wig-wag" is:
  • A A trailer hitch component
  • B A low-air pressure warning device that drops a flag in front of the driver
  • C A type of cargo strap
  • D A fuel-saving switch
Correct answer: B
On older trucks, a wig-wag is a mechanical low-air warning that lowers a flag into the driver's field of view when air pressure drops below safe limits.
Question 23 of 25
A driver's blood-alcohol concentration (BAC) of 0.04% or higher while operating a commercial motor vehicle is:
  • A Allowed if the driver feels fine
  • B Allowed off-duty only
  • C Considered driving under the influence for CDL purposes
  • D A traffic violation, but not a CDL disqualification
Correct answer: C
Federal rules treat 0.04% BAC in a CMV as DUI for CDL purposes — half the typical 0.08% limit for non-commercial drivers.
Question 24 of 25
A vehicle's "no-zone" is:
  • A The fuel tank area
  • B The area immediately next to it where other drivers are hidden in your blind spots
  • C The area in front of the steer axle
  • D A federal speed restriction
Correct answer: B
No-zones are the four blind-spot areas (front, rear, and both sides) where smaller vehicles are difficult or impossible to see in your mirrors.
Question 25 of 25
The proper following distance for a 60-foot truck traveling under 40 mph is at least:
  • A 6 seconds
  • B 1 second
  • C 4 seconds
  • D 10 seconds
Correct answer: A
Use one second per 10 feet of vehicle length below 40 mph: 60 ft / 10 = 6 seconds. Add one additional second above 40 mph.

Study tips for the Indiana General Knowledge exam

The General Knowledge 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 General Knowledge 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 General Knowledge.

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 General Knowledge 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 General Knowledge 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 Air Brakes · IN Combination Vehicles · 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.