CDL-10 Section 1 - Introduction
CDL-10 Section 1, Introduction, sets the foundation for the general-knowledge exam: which commercial motor vehicle needs which license class, what endorsements permit, and when a driver is disqualified. Questions here are often definition traps rather than driving scenarios.
License classes and endorsements
- Class A: combination vehicle with GCWR over 26,000 lb and towed unit over 10,000 lb.
- Class B: single vehicle over 26,000 lb, or such a vehicle towing 10,000 lb or less.
- Class C: designed to carry 16 or more passengers including the driver, or placarded hazmat, in a vehicle not Class A or B.
- Endorsements: T doubles/triples, P passengers, N tank, H hazmat, X tank plus hazmat, S school bus. An endorsement is added to a class; it does not replace the class.
Qualification and disqualification
A driver must hold a valid medical examiner's certificate and meet vision, hearing, and age rules. A CMV driver is considered alcohol-impaired at 0.04% BAC, not 0.08%. Refusing a test, leaving the scene, a felony involving a CMV, or driving with a suspended CDL can trigger major disqualification: one year for a first offense and lifetime for a second. Serious traffic violations include 15 mph or more over the limit, reckless driving, improper lane changes, following too closely, and texting or handheld phone use. Two serious violations in three years mean 60 days out of service; three mean 120 days.
Worked example
An applicant has a 28,000-lb truck and wants to tow a 12,000-lb trailer. Class B is not enough: the combined weight exceeds 26,000 lb and the towed unit exceeds 10,000 lb, so Class A is required. If the trailer were 9,000 lb, Class B could work.
Traps
Do not confuse 0.04% with the 0.08% non-CMV limit; do not treat an endorsement as a license class; and do not count only the tractor weight when deciding Class A.