Free, full Michigan 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. Matched to the official SOS knowledge exam.
Reaction distance is the distance your vehicle travels:
C. From when your brain recognizes a hazard until your foot pushes the brake — Reaction distance covers the roughly three-quarters of a second between recognizing danger and moving your foot to the brake pedal.
What is the purpose of checking the 'glad hand seals' (also called grommet seals) during a pre-trip inspection?
B. To ensure the rubber seals are in good condition to prevent air leaks when glad hands are connected — damaged seals cause air pressure loss and brake degradation — Glad hand seals (grommets) create an airtight connection between tractor and trailer air lines. Cracked, torn, or missing seals allow air to escape, potentially reducing brake effectiveness.
What is the minimum eyesight requirement to qualify for a CDL under 49 CFR Part 391?
B. At least 20/40 vision in each eye (with or without correction) and adequate field of vision — CDL applicants must have at least 20/40 acuity in each eye separately, with or without corrective lenses, and a field of vision of at least 70 degrees in the horizontal meridian in each eye.
You must use your headlights:
A. From a half hour after sunset to a half hour before sunrise and whenever visibility is low — Headlights are required from dusk to dawn and any time visibility drops, so other drivers can see you and you can see the road.
A trailer skid is most likely to occur when:
B. The trailer brakes lock up — Trailer skid occurs when the trailer brakes lock up and the trailer swings out. Unlike a jackknife, the trailer leads.
CDL safety scenario 8: What is the greatest risk when pulling doubles or triples?
C. Rearward amplification and rollover from quick steering — Rearward amplification and rollover from quick steering. Commercial drivers are expected to manage this situation before it becomes a crash risk. The CDL manual emphasizes controlling the vehicle, inspecting safety-critical systems, and correcting hazards promptly.
What is the proper way to use the clutch when starting from a stop on a hill (manual transmission)?
B. Use the parking brake to hold, then release as you engage the clutch — On a hill start, use the parking brake to prevent rollback. Release it smoothly as the clutch engages and the vehicle begins to move.
When should you use the trailer hand valve (trolley valve)?
D. Only to test trailer brakes — Use the trailer hand valve only for testing trailer brakes. Using it while driving can cause a trailer skid because only the trailer brakes apply.
What is the 'crack-the-whip' effect in doubles and triples combinations?
B. The amplified sway of each successive trailer — the last trailer sways much more than the one ahead of it — Like a whip, each trailer in a doubles/triples combination moves more than the one ahead during a lane change or swerve. The last trailer can sway several times the amount of the tractor's steering input.
During the in-cab inspection, check that the parking brake holds by:
B. Setting it and testing with gentle acceleration in low gear — Set the parking brake and try to move the vehicle gently in a low gear. The parking brake should hold the vehicle firmly.
The Michigan 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.
In Michigan, driver licensing is handled by the Michigan Secretary of State (SOS), so you'll often see the exam called the SOS CDL general knowledge test. The practice tests on this page match the official SOS knowledge exam format.
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.