Free, full Colorado 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.
What is the best way to test if your trailer is securely coupled before beginning a trip?
B. Apply the trailer brakes with the hand valve, then slowly pull forward to verify no separation — The tug test — applying the trailer brakes and gently pulling forward — is the best practical verification that the fifth wheel jaws are locked around the kingpin and the trailer is secure.
The Federal Bridge Formula is used to determine:
B. The maximum weight allowed based on the number and spacing of axles — The Federal Bridge Formula (also called Bridge Formula B) calculates the maximum legal weight based on the number of axles and the distance between the outer axles of any group, to protect bridge structures.
You should never load a liquid tank completely full because:
A. Liquids expand and need room — Leave outage (empty space) in liquid tanks because liquids expand with temperature changes. A full tank can rupture.
Hazardous materials a bus may NOT carry as passenger baggage include:
A. Tear gas, explosives, and most other hazardous materials — Buses are barred from carrying most hazardous materials, including explosives and tear gas, to protect the passengers aboard.
The biggest danger when hauling a liquid tanker is:
C. Surge and high center of gravity — Liquid surge and high center of gravity make tankers prone to rollovers, especially in turns and when braking.
Falsifying a logbook or electronic logging device (ELD) record is:
C. A serious violation that can lead to fines and being placed out of service — False duty records are illegal; they can bring fines, out-of-service orders, and disqualification, and they hide dangerous fatigue.
After placing warning triangles at a breakdown on a two-lane road, you should place one:
C. About 100 feet behind and 100 feet ahead, plus one at the vehicle — On a two-lane road, place triangles about 10 feet behind vehicle, 100 feet behind, and 100 feet ahead for bidirectional warning.
CDL safety scenario 71: When driving a long commercial vehicle, why should you make turns slowly?
B. Off-tracking can cause the rear wheels to cut across curbs or lanes — Off-tracking can cause the rear wheels to cut across curbs or lanes. 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.
When driving a tanker in windy conditions, you should:
D. Reduce speed and hold the wheel firmly — Tankers have a high center of gravity and large surface area, making them very susceptible to cross winds. Reduce speed and grip the wheel firmly.
CDL safety scenario 73: Why must cargo weight be balanced side to side?
D. Uneven weight can make the vehicle lean or roll over more easily — Uneven weight can make the vehicle lean or roll over more easily. 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.
The Colorado 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.