Oregon Combination Vehicles Practice Test
Required for a Class A license — tractor-trailers, truck-and-trailer combinations, anything articulated. The test concentrates on what makes combinations dangerous in ways straight trucks aren't: trailer sway and rollover thresholds, off-tracking in turns, jackknife causes and recovery, and the coupling/uncoupling sequence with fifth wheel, kingpin, and air/electrical lines. Expect several questions on the order of coupling steps and on glad-hand and trailer air-supply behavior, because getting those wrong in the real world drops a trailer.
Who needs it: Class A applicants. Class B drivers moving up to combinations take it then.
Sample practice questions
The service line is commonly coded ___ and the emergency line ___.
Answer: blue / red — Service is often blue; emergency is often red (to avoid mixing them up).
Before coupling, the fifth wheel should be:
Answer: Greased, tilted down toward the rear, jaws open, release handle unlocked — It must be greased, tilted down to the rear, jaws open, and the release handle in the unlocked position.
At the end of coupling you should:
Answer: Remove and store the wheel chocks safely — Remove and store the chocks once coupled and ready to move.
Common mistakes on the Combination test
- Learning coupling steps out of order — the exam tests the sequence, not just the parts
- Missing that the trailer hand valve is for TESTING, not for normal braking or parking
- Underestimating rearward amplification — the crack-the-whip effect on the last trailer
- Forgetting to check trailer height before backing under: too low crushes the nose, too high misses the kingpin
Studying with the full Truckcess course does double duty: the theory counts toward the federal ELDT requirement (Truckcess is listed on the FMCSA Training Provider Registry).
Official source: Oregon Driver & Motor Vehicle Services (ODOT)
CDL licensing in Oregon is administered by the Oregon Driver & Motor Vehicle Services (ODOT). Fees, scheduling, forms, and the official Oregon CDL manual live on the official site: Oregon DMV — official CDL page (verified 2026-08-09).
Truckcess is not affiliated with or endorsed by the Oregon Driver & Motor Vehicle Services (ODOT). Our practice tests cover the federal CDL knowledge standards (49 CFR Part 383) that every state exam is built on; exact question counts, fees, and procedures vary by state and change over time — the official site is always the authority.
More Oregon practice tests
Full prep courses are one-time from $59 with 12 months of access — mytruckcess.com/cdl.
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