South Dakota General Knowledge CDL Practice Test
Below are 25 exam-style questions for the South Dakota General Knowledge CDL knowledge test, modeled on the FMCSA-aligned content used by the South Dakota Driver Licensing Program. 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 Safety for yourself and other road users
- B To improve fuel economy
- C To meet your dispatcher's schedule
- D To reduce tire wear
- A A vehicle is in safe operating condition
- B Required emergency equipment is missing
- C A passenger door is open
- D A trailer brake light is out
- A Did not take the test, with no consequence
- B Need to take it again later
- C Took the test and passed
- D Took the test and failed
- A Brake-lag distance only
- B Reaction distance only
- C Speed times weight
- D Perception distance + reaction distance + brake-lag distance + braking distance
- A Signal only when other vehicles are present
- B Signal early, signal continuously, and cancel after the turn
- C Signal only at the moment you start turning
- D Use the four-way flashers instead of signals at intersections
- A 4/32 inch
- B 2/32 inch
- C 1/32 inch
- D 6/32 inch
- A Stay in high gear
- B Use the parking brake intermittently
- C Coast in neutral
- D Select a lower gear before starting down
- A Only when the load is hazardous
- B At the end of the trip
- C Within the first 25 miles, then about every 150 miles or every 3 hours
- D Only if a warning light comes on
- A Shift into reverse
- B Coast in neutral
- C Look for an escape ramp
- D Use the parking brake hard
- A Bridge surfaces freeze first because of air circulation underneath
- B The pavement under the bridge is reinforced
- C Bridges are inspected only in winter
- D The bridge is closed in winter
- A Checking the engine compartment
- B Adjusting the trailer brakes individually
- C Walking around the vehicle and checking lights
- D Testing the service and parking brakes
- A A low-air pressure warning device that drops a flag in front of the driver
- B A trailer hitch component
- C A type of cargo strap
- D A fuel-saving switch
- A No one
- B The dispatcher only
- C The carrier only
- D The driver, in the form of a logbook or electronic logging device
- A 10 hours
- B 11 hours
- C 16 hours
- D 14 hours
- A Three reflective triangles: 10 ft, 100 ft, and 200 ft toward approaching traffic
- B A flare burning constantly
- C One reflective triangle within 10 feet
- D A spotter walking 1,000 ft up the road
- A The fuel tank area
- B The area in front of the steer axle
- C The area immediately next to it where other drivers are hidden in your blind spots
- D A federal speed restriction
- A A red flag (or red light at night) at the extreme rear
- B Yellow tape only
- C Nothing — federal rules do not require marking
- D A green flag
- A It causes the engine to overheat
- B It can let poisonous carbon monoxide into the cab
- C It increases fuel use
- D It is illegal
- A All of the above
- B Brakes alone are not designed to hold a heavy vehicle on a long downgrade
- C Heavy vehicles can slow down sharply on grades
- D Engine braking helps keep speed under control
- A Cross at maximum speed to get over quickly
- B Always come to a full stop regardless of traffic
- C Slow down, look, listen, and be prepared to stop
- D Honk and proceed
- A Make eye contact only when stopped
- B Tap the horn lightly or flash lights to signal your presence
- C Never communicate; just drive
- D Honk loudly to warn other drivers
- A 40,000 lbs or more
- B 10,001 lbs or more
- C 26,001 lbs or more
- D 20,000 lbs or more
- A Gross Vehicle Weight Rating
- B Government Vehicle Weight Regulation
- C General Vehicle Weight Reading
- D Gross Vehicle Width Rating
- A Use high-beam headlights for maximum visibility
- B Use low-beam headlights and slow down
- C Use the four-ways while in motion at highway speed
- D Drive faster to get out of the fog quickly
- A 20 hours in a 24-hour period
- B 14 consecutive hours since coming on duty
- C 8 hours in any 24-hour period
- D 15 hours of driving
Study tips for the South Dakota General Knowledge exam
The General Knowledge portion of the South Dakota CDL exam is graded out of the bank of questions the South Dakota Driver Licensing Program draws from each year. While the exact bank is not published, every question is sourced from the General Knowledge chapter of the South Dakota 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 South Dakota 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 South Dakota Driver Licensing Program 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 South Dakota 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 South Dakota 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 South Dakota Driver Licensing Program office.
Already comfortable with this endorsement? Drill another: SD Air Brakes · SD Combination Vehicles · SD Hazardous Materials · SD Passenger · SD School Bus · SD Tank Vehicle · SD Doubles / Triples
New to the CDL process in South Dakota? Read How to apply for a CDL in South Dakota for the document checklist and step-by-step timeline.