Free, full Oklahoma CDL general knowledge test practice right here in your browser — real exam format (50 questions, 80% to pass), diagnostic and adaptive modes, spaced-repetition review, and a readiness dashboard. No signup, no paywall — your progress is saved automatically on this device.
A sign that one of your tires has failed is:
D. A loud bang, vibration, or the vehicle thumping or pulling to one side — A bang, sudden vibration, or pulling to one side often signals a blowout, so be ready to hold the wheel and slow down safely.
How often should you check your mirrors while driving a commercial vehicle?
C. Every 5-8 seconds — Check mirrors every 5-8 seconds to maintain awareness of your surroundings and traffic conditions.
Hazmat placards must be placed:
A. On all four sides of the vehicle — Placards go on all four sides so the material's hazard class is visible to responders and others from any direction.
What should you do if you discover a coupling problem (e.g., a cracked fifth wheel plate) during a pre-trip inspection?
B. Do not drive — report the defect to your supervisor and do not operate the vehicle until repairs are made — A defective fifth wheel plate is a critical safety defect. You must not operate the vehicle with a defective coupling device. Report it immediately and wait for repairs before operating.
What should you do if you notice a suspicious package or item left on the bus?
C. Treat it as a potential threat: do not touch it, evacuate passengers away from it, and call authorities — An unattended package on a bus should be treated as a potential threat. Do not touch or move it, evacuate passengers upwind and away, and contact law enforcement.
The best way to take a curve in a CMV is to:
A. Slow to a safe speed before the curve, then accelerate gently through it — Slow down before entering the curve. Braking in a curve can cause a skid. Gentle acceleration through the curve helps maintain stability.
Which of the following HazMat classes requires 'any quantity' placarding regardless of the amount carried?
C. Division 2.3 (poison gas) and Division 6.1 (poison inhalation hazard) — Certain HazMat classes require placarding in ANY quantity: Division 1.1, 1.2, 1.3 (explosives), Division 2.3 (poison gas), Class 7 (radioactive), and Division 6.1 (poison inhalation hazard). Most others require placards only at 1,001 lbs or more.
Under HOS rules, after 8 consecutive hours of driving, you must take a break of at least:
D. 30 minutes — After accumulating 8 hours of driving, federal HOS rules require at least a 30-minute off-duty break before driving again. The break can be taken as a sleeper berth period. Skipping it extends fatigue and violates regulations that can result in an out-of-service order.
An unbaffled (smooth-bore) liquid tank is MOST dangerous because:
B. Liquid surge is much worse since nothing slows the movement of liquid — Smooth-bore tanks have no internal dividers, so liquid can surge freely from one end to the other. This severe surge can push the vehicle in unexpected directions.
The maximum allowable BAC for a CDL holder driving a non-commercial vehicle is:
B. 0.08% — When driving a non-commercial vehicle, the standard BAC limit of 0.08% applies. The 0.04% limit only applies when operating a CMV.
The Oklahoma CDL general knowledge test has 50 questions, and you need 80% to pass — at least 40 correct answers. The practice tests on this page use the same format. The 80% passing score is a federal FMCSA standard used by every state.
80%. You can miss at most 10 of the 50 questions. The readiness dashboard on this page tracks whether you're consistently scoring above that bar.
Yes. Every practice test on this page and everything in the DMVPrep iPhone app is free — no ads, no paywall, no account.
Federal motor carrier safety regulations (FMCSA) — the same rules every state's CDL exam is drawn from. Every question in the DMVPrep app cites the regulation or handbook section it comes from.
Yes — the DMVPrep app includes all 3,745+ questions in Spanish, and the whole app works in Spanish.