CDL · Class A vs. Class B (License Class Selection) · United States

Class A vs. Class B (License Class Selection) for the CDL Exam — U.S. candidates

5% of the CDL test plan. Class A allows combination vehicles (truck + trailer >10,000 lb GVWR); Class B is single-vehicle only. Selecting the right class up-front saves money and matches career intent. Calibrated for American candidates.

If you have already studied this content from a textbook, you know the material. The question this page answers is whether you can apply it under exam conditions. Class A vs. Class B (License Class Selection) sits at roughly 5% of the Commercial Driver License content distribution — Class A is required for over-the-road tractor-trailer driving (the dominant CDL career path). Class B covers straight trucks, dump trucks, school buses, and most municipal vehicles. A Class A holder can drive any Class B vehicle (with appropriate endorsements); a Class B holder cannot drive Class A combinations. In 2024, the published first attempt rate for CDL candidates in United States was 65% (FMCSA / state DMV aggregate (representative figure)). For U.S. candidates preparing for CDL, the calibration of study to local context matters: U.S. licensure exams are governed at the state level (CDL, NCLEX) or by national boards (MCAT, GRE). Pearson VUE and PSI are the dominant test-delivery vendors.

Common failure modes

These are the patterns that cause most candidates to lose marks on this topic. Recognising them in advance is half the work.

  • !Choosing Class B because the training is shorter, then realising the desired employer requires Class A
  • !Confusing GCWR (combination weight rating) with GVWR (single vehicle weight rating)
  • !Not realising school bus drivers need a Class B with P+S endorsements (or Class A in larger districts)

Study tips

  • 1Check 5+ job postings for your target employer/role and confirm whether they require Class A or Class B before selecting your training program.
  • 2If undecided, choose Class A — it covers everything Class B does plus combination vehicles.
  • 3For local delivery and municipal jobs, Class B with appropriate endorsements (P, S, T, N, X, H) is often sufficient.
  • 4If you are testing in the U.S., expect CDL delivery via Pearson VUE or PSI test centres — register through the official board portal at least 30 days in advance.

Sample CDL Class A vs. Class B (License Class Selection) questions

These sample items mirror the format and difficulty of real CDL questions. Practice with thousands more on the free Koydo question bank.

  1. 1

    A driver wants to operate a tractor-trailer with a 70,000 lb GCWR. Which CDL class is required?

    • AClass ACorrect
    • BClass B
    • CClass C
    • DEither A or B
    Why this answer?

    Class A is required for any combination of vehicles with a GCWR of 26,001 lb or more, where the towed vehicle exceeds 10,000 lb GVWR. A 70,000 lb GCWR tractor-trailer falls under Class A.

Frequently asked questions

Can a Class A holder drive a Class B vehicle?
Yes — a Class A CDL allows operation of Class B and Class C vehicles, provided the driver holds the necessary endorsements (e.g., P for passengers, S for school bus, H or X for hazardous materials).
What is the CDL Class A vs. Class B (License Class Selection) pass rate for American candidates?
The published first attempt rate for CDL candidates in United States in 2024 was 65%, according to FMCSA / state DMV aggregate (representative figure). Pass rates within specific topics like Class A vs. Class B (License Class Selection) are not separately published, but the topic represents roughly 5% of the exam.
How long should American candidates study Class A vs. Class B (License Class Selection) for the CDL?
For most candidates, focused mastery of Class A vs. Class B (License Class Selection) requires 20–40 hours of deliberate practice — drilling sample questions, reviewing failure modes, and timing yourself against exam conditions. U.S. licensure exams are governed at the state level (CDL, NCLEX) or by national boards (MCAT, GRE). Pearson VUE and PSI are the dominant test-delivery vendors. Combine Class A vs. Class B (License Class Selection) study with full-length mock exams in the final two weeks before your test date.

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Related study guides

Regulatory citation: 49 CFR §383.91 — Commercial motor vehicle groups.