Career upgrade: Learn practical AI skills for better jobs and higher pay.
Level up
PracticeVideosBlogFlashcardsEspañol
All Practice Exams

200+ Free Illinois CDL Combination Practice Questions

Pass your Illinois CDL Combination Vehicles Test exam on the first try — instant access, no signup required.

✓ No registration✓ No credit card✓ No hidden fees✓ Start practicing immediately
200+ Questions
100% Free
1 / 200
Question 1
Score: 0/0

What should be verified about the fifth wheel plate before coupling?

A
B
C
D
to track
Same family resources

Explore More CDL Combination Vehicles Test

Continue into nearby exams from the same family. Each card keeps practice questions, study guides, flashcards, videos, and articles in one place.

Alabama CDL Combination Vehicles Test

Practice Questions

Alaska CDL Combination Vehicles Test

Practice Questions

Arizona CDL Combination Vehicles Test

Practice Questions

Arkansas CDL Combination Vehicles Test

Practice Questions

California CDL Combination Vehicles Test

Practice Questions

Colorado CDL Combination Vehicles Test

Practice Questions
2026 Statistics

Key Facts: Illinois CDL Combination Exam

80%

Minimum federal passing score for each CDL knowledge test

49 CFR §383.135

14 days

Minimum Illinois CLP holding period before Class A skills and drive testing

Illinois Secretary of State CDL/CLP page

26,001 lb

Class A GCWR threshold when the towed unit is over 10,000 lb GVWR

Illinois Secretary of State CDL/CLP page

1 year

Illinois CLP validity from temporary card issuance

Illinois Secretary of State CDL/CLP page

Illinois Class A CDL applicants must pass Combination Knowledge written testing, usually alongside General Knowledge and any required Air Brake or endorsement tests. Study Illinois CDL Study Guide combination-vehicle material and FMCSA CDL Manual Section 6: fifth wheel and kingpin coupling, tug and visual checks, air/electric lines, landing gear, trailer brakes, off-tracking, rollover, backing, trailer skids, jackknife recovery, and safe speed and space management. Federal CDL rules require at least 80% correct on each knowledge test, and failing the combination portion blocks Group A CLP/CDL issuance.

Sample Illinois CDL Combination Practice Questions

Try these sample questions to test your Illinois CDL Combination exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 200+ question experience with AI tutoring.

1Which Illinois CDL written test is required for drivers seeking Class A combination-vehicle privileges?
A.The Combination Knowledge written test
B.Use only the trailer hand valve for normal stopping
C.Skip the visual inspection if the vehicle moves during a tug test
D.Drive at normal speed and correct problems after the trip
Explanation: Illinois says Class A applicants must pass Combination Knowledge written testing, plus General Knowledge and any applicable Air Brake or endorsement tests. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
2In Illinois CDL classification rules, Class A generally means GCWR of 26,001 pounds or more when the towed unit is over what GVWR?
A.Use only the trailer hand valve for normal stopping
B.10,000 pounds
C.Skip the visual inspection if the vehicle moves during a tug test
D.Drive at normal speed and correct problems after the trip
Explanation: Illinois lists Class A as a qualifying combination when the towed vehicle has GVWR over 10,000 pounds. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
3What does GCWR stand for?
A.Use only the trailer hand valve for normal stopping
B.Skip the visual inspection if the vehicle moves during a tug test
C.Gross Combination Weight Rating
D.Drive at normal speed and correct problems after the trip
Explanation: GCWR is Gross Combination Weight Rating, the combined rating used for tractor-trailer and other combination classifications. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
4What does GVWR stand for?
A.Use only the trailer hand valve for normal stopping
B.Skip the visual inspection if the vehicle moves during a tug test
C.Drive at normal speed and correct problems after the trip
D.Gross Vehicle Weight Rating
Explanation: GVWR is Gross Vehicle Weight Rating, the rating assigned to a single vehicle or towed unit. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
5What minimum score is required on CDL knowledge tests under 49 CFR 383.135?
A.80 percent correct
B.Use only the trailer hand valve for normal stopping
C.Skip the visual inspection if the vehicle moves during a tug test
D.Drive at normal speed and correct problems after the trip
Explanation: Federal CDL rules require at least 80 percent correct on each knowledge test. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
6Who administers Illinois CDL and CLP testing logistics?
A.Use only the trailer hand valve for normal stopping
B.Illinois Secretary of State Driver Services
C.Skip the visual inspection if the vehicle moves during a tug test
D.Drive at normal speed and correct problems after the trip
Explanation: FMCSA sets federal minimum standards, but Illinois Secretary of State Driver Services administers Illinois CDL testing. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
7What is a combination vehicle?
A.Use only the trailer hand valve for normal stopping
B.Skip the visual inspection if the vehicle moves during a tug test
C.A truck or tractor pulling one or more trailers
D.Drive at normal speed and correct problems after the trip
Explanation: A combination vehicle is a powered unit pulling one or more trailers, such as a tractor-semitrailer. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
8What extra area must be inspected on a combination vehicle compared with a straight truck?
A.Use only the trailer hand valve for normal stopping
B.Skip the visual inspection if the vehicle moves during a tug test
C.Drive at normal speed and correct problems after the trip
D.The coupling area between tractor and trailer
Explanation: Combination inspections add the fifth wheel, kingpin, locking jaws, air lines, electrical cord, landing gear, and trailer condition. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
9Why must trailer lights be checked after coupling?
A.To confirm other traffic can see trailer clearance, turns, brake lights, and hazards
B.Use only the trailer hand valve for normal stopping
C.Skip the visual inspection if the vehicle moves during a tug test
D.Drive at normal speed and correct problems after the trip
Explanation: The electrical connection must operate required trailer lights and signals. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.
10Before driving, what should be true of the landing gear?
A.Use only the trailer hand valve for normal stopping
B.It is fully raised and the handle is secured
C.Skip the visual inspection if the vehicle moves during a tug test
D.Drive at normal speed and correct problems after the trip
Explanation: Landing gear must be raised completely and secured before the combination moves. Source basis: Illinois Secretary of State CDL/CLP guidance, the Illinois CDL Study Guide, FMCSA CDL Manual Section 6, and 49 CFR Part 383.

About the Illinois CDL Combination Exam

The Illinois CDL Combination Vehicles Test is the written knowledge test for drivers seeking Class A commercial driving privileges for qualifying tractor-trailer and other combination vehicles. Illinois requires the Combination Knowledge written test for Class A applicants and points drivers to its CDL Study Guide, while FMCSA Part 383 supplies federal Group A vehicle standards and the 80% minimum knowledge-test passing score. The tested knowledge centers on combination inspection, fifth wheel and kingpin coupling, air and electrical lines, landing gear, trailer brakes, off-tracking, rollover prevention, safe turns, backing, trailer skids, jackknife recovery, speed, and space management.

Assessment

Computerized multiple-choice CDL knowledge test for Class A combination applicants; Illinois requires Combination Knowledge written testing for Class A privileges, plus General Knowledge and any applicable Air Brake or endorsement tests.

Time Limit

No separate Illinois Secretary of State time limit is published for the Combination Vehicles knowledge test

Passing Score

80% on each CDL knowledge test under 49 CFR §383.135

Exam Fee

$50 CLP fee for applicants adding a CLP to an Illinois non-CDL; some upgrades or endorsement/restriction changes requiring an original CLP are listed at $5 (Illinois Secretary of State Driver Services)

Illinois CDL Combination Exam Content Outline

Core section

Driving Combination Vehicles Safely

Rollover risk, high center of gravity, steering response, rearward amplification, off-tracking, wide turns, low-clearance railroad crossings, backing, trailer swing, and space management.

Core section

Combination Vehicle Air Brakes

Trailer hand valve, tractor protection valve, trailer air supply control, service and emergency lines, glad hands, crossed-line faults, trailer ABS, leaks, and trailer brake tests.

Core section

Coupling and Uncoupling

Fifth wheel plate and jaws, kingpin, trailer height, high coupling, tug test, visual inspection, air/electrical line connection, landing gear, chocks, and safe release sequence.

Core section

Inspecting Combination Vehicles

Coupling area, trailer frame, suspension, brakes, tires, lights, reflectors, landing gear, cargo doors, load security, and post-coupling final checks.

Licensing section

Illinois CDL and FMCSA Rules

Illinois Class A combination requirements, CLP fees and validity, 14-day CLP holding period, FMCSA state agency role, Group A vehicle rules, and federal 80% passing standard.

How to Pass the Illinois CDL Combination Exam

What You Need to Know

  • Passing score: 80% on each CDL knowledge test under 49 CFR §383.135
  • Assessment: Computerized multiple-choice CDL knowledge test for Class A combination applicants; Illinois requires Combination Knowledge written testing for Class A privileges, plus General Knowledge and any applicable Air Brake or endorsement tests.
  • Time limit: No separate Illinois Secretary of State time limit is published for the Combination Vehicles knowledge test
  • Exam fee: $50 CLP fee for applicants adding a CLP to an Illinois non-CDL; some upgrades or endorsement/restriction changes requiring an original CLP are listed at $5

Keys to Passing

  • Complete 500+ practice questions
  • Score 80%+ consistently before scheduling
  • Focus on highest-weighted sections
  • Use our AI tutor for tough concepts

Illinois CDL Combination Study Tips from Top Performers

1Start with the Illinois CDL Study Guide and focus on combination-vehicle material before drilling practice questions.
2Turn the coupling sequence into a checklist: inspect fifth wheel, align, check trailer height, back under, tug test, visual lock check, connect lines, charge air, test brakes, raise landing gear, and remove chocks.
3Memorize red emergency/supply and blue service glad-hand functions, then practice crossed-line and leak scenarios.
4Study control risks as cause-and-effect: speed plus high center of gravity increases rollover, hard braking can lock trailer wheels, and off-tracking makes trailer wheels cut inside turns.
5Before testing, confirm Illinois CLP documents, fees, medical self-certification, ELDT status, and appointment rules on the Secretary of State CDL page.

Frequently Asked Questions

Who needs the Illinois CDL Combination Vehicles test?

Drivers seeking Illinois Class A privileges for qualifying combination vehicles need Combination Knowledge written testing unless an Illinois transfer or waiver rule applies. Illinois defines Class A by GCWR of 26,001 or more pounds when the towed vehicle has GVWR over 10,000 pounds.

What score do I need to pass?

49 CFR §383.135 requires at least 80% correct on each CDL knowledge test. The same section states that an applicant who fails the combination-vehicle portion must not be issued a Group A CLP or CDL.

What topics are on the Illinois combination test?

Study combination-vehicle inspection, fifth wheel and kingpin coupling, trailer height, tug and visual checks, air and electrical lines, landing gear, trailer brake controls, off-tracking, rollover, safe turns, backing, trailer skids, jackknife recovery, and speed/space management.

How long must I hold an Illinois Class A CLP before skills testing?

Illinois says applicants upgrading to or obtaining Class A combination privileges must hold the Class A CLP for at least 14 days before skills and drive testing.

How much does the Illinois CDL combination test cost?

Illinois publishes CLP/CDL transaction fees rather than a separate Combination Vehicles-only fee. The Secretary of State page lists a $50 CLP fee for applicants adding a CLP to an Illinois non-CDL and $5 for some CDL upgrades or endorsement/restriction changes requiring an original CLP.