New Jersey CDL — General Knowledge practice
Traffic Laws
Speed limits, turning and signaling rules, headlight and seat-belt requirements, and the everyday laws every driver must follow.
Questions reviewed against the official New Jersey driver handbook · July 7, 2026
15 questions · pass with 12 correct. You get instant feedback and an explanation after every answer.
Study questions with answers
12 sample Traffic Laws questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.
1. Within 30 days you must tell your own state's licensing agency about a conviction for a traffic violation committed in another jurisdiction. When does this rule apply?
Correct answer: For any traffic conviction except parking, in any vehicle
The rule covers any traffic conviction (except parking) in another jurisdiction, no matter what kind of vehicle you were driving at the time.
Source: New Jersey CDL Manual — Section 1: Introduction (Other CDL Rules)
2. How often must a driver hauling cargo re-check that the load is secure after the first inspection?
Correct answer: After 3 hours or 150 miles, whichever comes first, and after each break
After the first 50 miles, cargo must be re-checked after driving 3 hours or 150 miles, whichever comes first, and after every break.
Source: New Jersey CDL Manual — Section 3: Transporting Cargo Safely (Inspecting Cargo)
3. How is the air brakes knowledge test triggered for a CDL applicant?
Correct answer: It applies to any vehicle equipped with air brakes
Anyone whose vehicle is equipped with air brakes, including air-over-hydraulic brakes, must pass the air brakes knowledge test.
Source: New Jersey CDL Manual — Section 1: Introduction (Knowledge Tests)
4. How soon must a driver inform their employer if their license is suspended, revoked, canceled, or they are disqualified from driving?
Correct answer: Within two business days
A loss of driving privileges or a disqualification must be reported to the employer within two business days.
Source: New Jersey CDL Manual — Section 1: Introduction (Other CDL Rules)
5. Under federal rules, how many driver's licenses may a CDL holder legally have at one time?
Correct answer: One
A commercial driver is limited to a single license; holding more than one can bring a fine of up to $5,000 or jail, and extra licenses are surrendered.
Source: New Jersey CDL Manual — Section 1: Introduction (Other CDL Rules)
6. If a driver operates in both interstate and intrastate commerce, which status must they choose when self-certifying?
Correct answer: Interstate commerce
A driver who works in both interstate and intrastate commerce must certify for interstate commerce, the more demanding of the two.
Source: New Jersey CDL Manual — Section 1: Introduction (Interstate or Intrastate Commerce)
7. What is the rule about wearing a safety belt while operating a commercial motor vehicle?
Correct answer: A safety belt must be worn at all times while driving
A driver has to stay buckled into a safety belt the whole time a CMV is being operated; the belt keeps the driver in control during a crash and lowers injury risk.
Source: New Jersey CDL Manual — Section 1: Introduction (Other CDL Rules)
8. Most CDL holders driving in non-excepted interstate commerce are required to provide their state agency with what document?
Correct answer: A current medical examiner's certificate
Non-excepted interstate drivers must give their licensing agency a current medical examiner's certificate, commonly called a DOT medical card.
Source: New Jersey CDL Manual — Section 1: Introduction (Interstate or Intrastate Commerce)
9. Within how many days must a CDL holder tell their employer about a conviction for a traffic violation (other than parking) in any vehicle?
Correct answer: Within 30 days
Drivers must notify their employer within 30 days of being convicted of any traffic offense besides parking, regardless of which vehicle they were driving.
Source: New Jersey CDL Manual — Section 1: Introduction (Other CDL Rules)
10. A tank endorsement is required to haul liquid or gas in a tank of what size?
Correct answer: Individual capacity over 119 gallons and aggregate of 1,000 gallons or more
The tank endorsement covers any tank whose single rated capacity tops 119 gallons while the combined rating reaches 1,000 gallons or above, even when the liquid is not hazardous.
Source: New Jersey CDL Manual — Section 1: Introduction (Commercial Driver License Tests)
11. When applying for a commercial driving job, how many years of previous driving-job history must you provide?
Correct answer: The past 10 years
An applicant must give the prospective employer information on every driving job held over the previous ten years.
Source: New Jersey CDL Manual — Section 1: Introduction (Other CDL Rules)
12. Which knowledge test must every CDL applicant take, regardless of vehicle class or endorsements?
Correct answer: The general knowledge test
The general knowledge test is required of all applicants; other tests such as air brakes or passenger transport apply only to specific vehicles or endorsements.
Source: New Jersey CDL Manual — Section 1: Introduction (Knowledge Tests)
More CDL — General Knowledge topics
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Every New Jersey question is written from the official New Jersey driver handbook and checked against its current edition. DMV Test Free is a free, independent study resource — not affiliated with any DMV or government agency. About DMV Test Free