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

200+ Free OR CDL Combination Practice Questions

Pass your Oregon 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

The “crack-the-whip” effect is mainly caused by:

A
B
C
D
to track
2026 Statistics

Key Facts: OR CDL Combination Exam

80%

Minimum CDL knowledge-test passing score

49 CFR §383.135 / FMCSA

At least 30

Minimum items on each basic vehicle-group knowledge test

49 CFR §383.133 / FMCSA

6 months

Oregon knowledge-test result validity

Oregon DMV

$10

Oregon CDL knowledge test fee

Oregon DMV Commercial Driver License Fees

$40

Original Oregon CLP fee on or after January 1, 2024

Oregon DMV Commercial Driver License Fees

English only

Oregon commercial knowledge-test language

Oregon DMV

Use Oregon Commercial Driver Manual Section 6 as the primary study source for the Oregon CDL Combination Vehicles Test. Focus on off-tracking, wide turns, rollover prevention, backing, trailer skids, jackknife recovery, trailer air supply and service lines, glad hands, tractor protection valves, fifth wheel and kingpin coupling, tug and visual checks, landing gear, and combination inspection. Oregon lists a $10 CDL knowledge test fee and six-month validity for passed knowledge-test results. Federal CDL rules require at least 80% correct, and a failed combination-vehicle knowledge test prevents Group A CLP/CDL issuance.

Sample OR CDL Combination Practice Questions

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

1Under Oregon CDL rules, the Combination Vehicles Test is required for drivers seeking to operate which vehicles?
A.Only passenger buses
B.Class A combination vehicles
C.Only tank vehicles
D.Motorcycles with trailers
Explanation: Oregon DMV lists the Combination Vehicles Test as required to drive Class A combination vehicles. Class A generally covers qualifying truck-trailer combinations rather than buses, tank endorsements alone, or motorcycles.
2A Group A/Class A combination generally means a combination with a GCWR of at least 26,001 pounds and a towed unit over:
A.5,000 pounds
B.8,000 pounds
C.10,000 pounds
D.20,000 pounds
Explanation: 49 CFR 383.91 defines Group A combinations using 26,001 pounds or more GCWR or gross combination weight, inclusive of a towed unit over 10,000 pounds.
3What is the best way to reduce rollover risk in a loaded combination vehicle?
A.Keep cargo high and drive normally
B.Keep cargo low and slow before turns
C.Brake hard while turning
D.Use the trailer hand valve through curves
Explanation: Oregon Section 6 says rollover prevention depends on keeping cargo as low and centered as possible and driving slowly around corners, ramps, and off-ramps.
4The “crack-the-whip” effect is mainly caused by:
A.Rearward amplification after quick steering
B.Too much fifth-wheel grease
C.Low engine coolant
D.A trailer door left open
Explanation: Rearward amplification means trailer movement becomes more severe toward the rear of the combination after quick steering, which can roll a trailer.
5Oregon Section 6 recommends following at least one second for each 10 feet of vehicle length, plus one extra second when traveling over:
A.25 mph
B.35 mph
C.40 mph
D.55 mph
Explanation: The Oregon manual states to follow at least 1 second for each 10 feet of vehicle length, plus another second if going over 40 mph.
6What is off-tracking?
A.The trailer wheels follow a shorter path than the tractor in a turn
B.The tractor engine loses power uphill
C.The air lines disconnect during backing
D.The fifth wheel slides forward by itself
Explanation: Off-tracking occurs when the trailer rear wheels follow a path inside the tractor path during turns, so the driver must allow extra room.
7When making a right turn with a tractor-trailer, you should mainly watch for:
A.The trailer cutting inside the tractor path
B.The trailer turning wider than the tractor
C.The kingpin unlocking automatically
D.The service line changing color
Explanation: Because the trailer off-tracks, its rear wheels cut inside the tractor path and can strike curbs, signs, or pedestrians if the turn is too tight.
8During a left turn in a combination vehicle, why should you monitor the left side carefully?
A.Cars or motorcycles may try to pass on the left
B.The trailer air tank may overfill
C.The landing gear lowers in left turns
D.The fifth wheel must be unlocked
Explanation: Combination drivers must watch for vehicles trying to pass on the left during left turns while also clearing the trailer path.
9Before entering a sharp curve with a heavy combination, the safest approach is to:
A.Slow to a safe speed before the curve
B.Maintain speed and brake in the curve
C.Accelerate to keep the trailer straight
D.Use only the trailer brakes
Explanation: Oregon Section 6 emphasizes slowing to a safe speed before turns and curves because rollovers happen when combinations turn too fast.
10Which backing setup is generally preferred for a combination vehicle when available?
A.Blind-side backing
B.Driver-side backing
C.Backing from the passenger seat
D.Backing without checking mirrors
Explanation: Driver-side backing gives the driver better sight lines to the trailer path. Blind-side backing should be avoided when a safer setup is available.

About the OR CDL Combination Exam

The Oregon CDL Combination Vehicles Test is the commercial knowledge test Oregon Class A applicants need for tractor-trailer and other qualifying combination operation. Oregon DMV directs applicants to the Oregon Commercial Driver Manual for commercial knowledge tests and lists the Combination Vehicles Test as required to drive Class A combination vehicles. Section 6 covers rollover risk, center of gravity, rearward amplification, steering gently, following distance, off-tracking, wide turns, low-clearance railroad crossings, backing, trailer skids and jackknife recovery, trailer air supply and service lines, glad hands, tractor protection valves, trailer ABS, coupling and uncoupling, fifth wheel and kingpin inspections, landing gear, and combination brake checks. FMCSA Part 383 supplies the federal Group A classification, required combination knowledge areas, test methods, and 80% knowledge-test passing standard.

Assessment

Oregon DMV lists the Combination Vehicles Test as required to drive Class A combination vehicles. Oregon Commercial Driver Manual Section 6 covers driving combinations, combination air brakes, ABS, coupling and uncoupling, and inspecting combinations. FMCSA requires basic vehicle-group knowledge tests to contain at least 30 items and to meet Part 383 standards.

Time Limit

Not published by Oregon DMV or FMCSA for the Combination Vehicles knowledge test

Passing Score

80% minimum on CDL knowledge tests under 49 CFR §383.135

Exam Fee

$10 CDL knowledge test; $40 original Commercial Learner Permit on or after January 1, 2024 (Oregon Driver and Motor Vehicle Services (DMV))

OR CDL Combination Exam Content Outline

Oregon CDL Manual Section 6.1

Driving Combination Vehicles Safely

Rollover risk, high center of gravity, rearward amplification, steering gently, off-tracking, wide turns, low-clearance railroad crossings, backing, trailer skids, jackknife recovery, following distance, and night speed.

Oregon CDL Manual Section 6.2

Combination Vehicle Air Brakes

Trailer hand valve, red emergency/supply and blue service lines, glad hands, crossed-line faults, air leaks, tractor protection valve, air flow to trailers, trailer emergency brakes, and trailer service brake tests.

Oregon CDL Manual Section 6.3

Antilock Brake Systems

ABS warning lamps, wheel-lock prevention, trailer ABS limits, and safe braking expectations for combinations.

Oregon CDL Manual Section 6.4

Coupling and Uncoupling

Fifth wheel plate and jaws, kingpin, trailer height, high coupling, tug test, no-gap visual inspection, air/electrical line connection, landing gear, chocks, and safe uncoupling sequence.

Oregon CDL Manual Section 6.5

Inspecting Combination Vehicles

Lower and upper fifth wheel, sliding fifth wheel, release arm and safety latch, air/electric lines, trailer frame, suspension, tires, lights, reflectors, landing gear, cargo doors, load security, and combination brake checks.

Oregon DMV/FMSCA logistics

Oregon CDL and FMCSA Rules

Oregon Class A testing, English-only commercial knowledge tests, $10 CDL knowledge test fee, six-month knowledge-test result validity, ELDT triggers, Group A vehicle thresholds, federal test-method rules, and 80% passing standard.

How to Pass the OR CDL Combination Exam

What You Need to Know

  • Passing score: 80% minimum on CDL knowledge tests under 49 CFR §383.135
  • Assessment: Oregon DMV lists the Combination Vehicles Test as required to drive Class A combination vehicles. Oregon Commercial Driver Manual Section 6 covers driving combinations, combination air brakes, ABS, coupling and uncoupling, and inspecting combinations. FMCSA requires basic vehicle-group knowledge tests to contain at least 30 items and to meet Part 383 standards.
  • Time limit: Not published by Oregon DMV or FMCSA for the Combination Vehicles knowledge test
  • Exam fee: $10 CDL knowledge test; $40 original Commercial Learner Permit on or after January 1, 2024

Keys to Passing

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

OR CDL Combination Study Tips from Top Performers

1Read Oregon Commercial Driver Manual Section 6 before using practice questions; it is the source Oregon DMV identifies for combination-vehicle test knowledge.
2Write a coupling checklist that includes fifth wheel condition, trailer height, kingpin, locking jaws, tug test, no-gap visual inspection, release arm, air/electric lines, trailer brake tests, and landing gear.
3Memorize the difference between red emergency/supply and blue service air lines, then practice crossed-line, air-leak, tractor-protection-valve, and trailer brake test scenarios.
4For control questions, connect the hazard to the response: slow before curves, steer gently, leave length-based following distance, avoid sudden lane changes, and release brakes during trailer-wheel skid recovery.
5Keep air-brakes-only depth separate from combination-specific brake topics unless your Oregon Class A vehicle also requires the Air Brakes Test.
6Review Oregon logistics before test day: English-only commercial knowledge testing, $10 CDL knowledge test fee, six-month result validity, and ELDT requirements before covered Class A skills testing.

Frequently Asked Questions

Who needs the Oregon CDL Combination Vehicles Test?

Oregon DMV lists the Combination Vehicles Test as required to drive Class A combination vehicles. Federal Group A/Class A rules generally cover combinations of 26,001 pounds or more GCWR or actual gross combination weight with a towed unit over 10,000 pounds.

What score do I need to pass?

FMCSA and 49 CFR §383.135 require at least 80 percent correct on CDL knowledge tests. The same rule states that an applicant who fails the combination-vehicle portion must not be issued a Group A CLP or CDL.

What should I study for the Oregon combination test?

Study Oregon Commercial Driver Manual Section 6: driving combinations safely, rollover risk, rearward amplification, off-tracking, turns, backing, trailer skids, combination air brakes, ABS, coupling and uncoupling, fifth wheel and kingpin checks, landing gear, and inspecting combinations.

How much does Oregon CDL knowledge testing cost?

Oregon DMV fee materials list a $10 CDL knowledge test fee and a $40 original Commercial Learner Permit fee on or after January 1, 2024. Check Oregon DMV for current CDL license, endorsement, skills-test, medical, and training costs.

How long are passed Oregon CDL knowledge-test results valid?

Oregon DMV states knowledge-test results are valid for six months from the date passed. CLP applicants must complete all application requirements within those six months or take and pass the knowledge tests again.

Are Oregon commercial knowledge tests available with a translator?

No. Oregon DMV states commercial knowledge tests are offered in English only and translators are not permitted.

Is the doubles/triples endorsement the same as the combination test?

No. Oregon Section 6 covers the minimum knowledge for common combination vehicles. Oregon DMV lists the Doubles/Triples Endorsement Test separately, and Section 6 tells drivers to study Section 7 if they need to pass the doubles/triples test.