Florida Combination Vehicles CDL Practice Test
Below are 25 exam-style questions for the Florida Combination Vehicles CDL knowledge test, modeled on the FMCSA-aligned content used by the Florida Department of Highway Safety and 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 Should be replaced when worn beyond manufacturer specs
- B Are normal until the lining is gone
- C Make the truck quieter
- D Only need attention every 5 years
- A The parking brake
- B Both tractor and trailer brakes simultaneously
- C The tractor service brakes only
- D The trailer service brakes only
- A Backing too fast
- B All of the above
- C Failure to grease
- D Coupling with the trailer too high
- A Fully raised before driving
- B Disconnected before driving
- C Lowered to the ground while driving
- D Always halfway extended
- A Disconnect the air supply
- B Accelerate
- C Release the brakes to allow the trailer wheels to roll again, then steer
- D Apply the trailer hand valve harder
- A Worn out tires
- B Cargo movement
- C Driving too fast for conditions and/or too closely
- D Engine failure
- A Driving off the road
- B Sliding sideways
- C Loss of traction
- D The trailer wheels follow a tighter arc than the tractor wheels in a turn
- A The fifth wheel breaks
- B The tractor brakes lock up
- C A wheel bearing fails
- D The trailer brakes lock up
- A Misalignment between tractor and trailer
- B Loose or missing fifth-wheel mounting bolts
- C All of the above
- D Cracks in the kingpin
- A Back without using mirrors
- B Back to the left whenever possible because you can see better
- C Back as fast as practical
- D Always back to the right
- A The trailer is too heavy
- B The fifth wheel disengages
- C The drive wheels lose traction and the tractor begins to slide
- D The tractor parking brake fails
- A The trailer wheels lock briefly
- B You are driving slowly
- C The drive wheels lock and the trailer pushes the tractor sideways
- D The brakes are released gently
- A 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
- B Use the shoulder
- C Stop traffic by signaling left
- D Turn from the left lane
- A Lower landing gear, disconnect lines, release fifth wheel, pull tractor away
- B Pull tractor away first, then disconnect lines
- C No specific order is required
- D Release fifth wheel first, then connect lines
- A Sends air pressure to apply trailer service brakes
- B Sends supply air to the trailer reservoirs
- C Carries electrical power
- D Drains the trailer reservoir
- A Brake adjustment levers
- B Coupling devices for connecting tractor air lines to the trailer
- C Electrical connectors
- D Manual transmission shifters
- A Stopping distances are normal
- B Stopping distances increase and the trailer can swing
- C Steering becomes easier
- D No effect on safety
- A By pushing in the red trailer-air-supply valve
- B By setting the red trailer-air-supply valve
- C By pulling out the red trailer-air-supply valve
- D By the trailer hand valve
- A Too high — it can damage the kingpin or skip over the fifth wheel
- B Loaded
- C Empty
- D Properly chocked
- A Use blocks instead
- B Lower the landing gear all the way until firmly on the ground, then a few extra cranks
- C Leave the gear up
- D Raise the gear partway
- A Drain the air tanks
- B Lower the trailer landing gear and chock the trailer wheels
- C Honk the horn
- D Disconnect the electrical line first
- A Only at the start of the day
- B Before, during, and after coupling
- C Only at the destination
- D Every 3 hours
- A A height where the tractor will lift the trailer slightly when backing under
- B A height that requires the tractor to drop down to fit
- C Maximum legal height
- D Whatever height it happens to be
- A All of the above
- B They have a higher rollover risk
- C They take more skill to back, couple, and uncouple
- D They are heavier and longer
- A All of the above
- B Off-tracking on right turns
- C Trailer sway in crosswinds
- D Reduced visibility along the trailer
Study tips for the Florida Combination Vehicles exam
The Combination Vehicles portion of the Florida CDL exam is graded out of the bank of questions the Florida Department of Highway Safety and Motor Vehicles draws from each year. While the exact bank is not published, every question is sourced from the Combination Vehicles chapter of the Florida 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 Florida 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 Florida Department of Highway Safety and 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 Florida 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 Florida 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 Florida Department of Highway Safety and Motor Vehicles office.
Already comfortable with this endorsement? Drill another: FL General Knowledge · FL Air Brakes · FL Hazardous Materials · FL Passenger · FL School Bus · FL Tank Vehicle · FL Doubles / Triples
New to the CDL process in Florida? Read How to apply for a CDL in Florida for the document checklist and step-by-step timeline.