How many questions are on the Pennsylvania CDL General Knowledge test?

50 questions. You must answer at least 40 correctly (80%) to pass. This test is required for every CDL applicant regardless of class or endorsement.

How many questions are on the Pennsylvania CDL Combination Vehicles test?

20 questions, requiring 16 correct (80%) to pass. Required for Class A CDL applicants who will operate combination vehicles.

What languages are Pennsylvania CDL knowledge tests given in?

English and Spanish. This is a genuine distinction from several other states, which offer knowledge testing in English only.

What happens if I fail a Pennsylvania CDL knowledge test?

You can retake it at a PennDOT Driver License Center. Confirm current retest wait times and fees directly with your local Driver License Center, since these can vary.

Pennsylvania CDL Test Questions 2026: Full Guide

Q: How many questions are on the Pennsylvania CDL Air Brakes test?

25 questions, requiring 20 correct (80%) to pass. Required if your vehicle has air brakes. Skipping the air brake check during the skills test is an automatic fail.

All three Pennsylvania CDL knowledge tests use the same 80% passing threshold. Pennsylvania also stands out for offering testing in Spanish, not just English — a genuine difference from several other states.

General Knowledge Test

50 Questions 40 to Pass (80%) Required for All Applicants

Covers vehicle inspection, basic vehicle control, driving safety, cargo transport, hazardous materials awareness, night driving and adverse conditions, emergency procedures, speed management, and Pennsylvania-specific rules. Required for every CDL applicant, regardless of class or endorsements.

Air Brakes Test

25 Questions 20 to Pass (80%) Required for Air Brake Vehicles

Covers air brake system basics, dual air brake systems, inspecting air brakes, using air brakes correctly, spring brakes and parking brakes, and malfunctions/emergencies. Required if your vehicle has air brakes.

Skipping the air brake check ("LAB" inspection) during the skills test is an automatic fail — this written test builds the foundation for that hands-on requirement.

Combination Vehicles Test

20 Questions 16 to Pass (80%) Required for Class A

Covers coupling and uncoupling, inspecting combination vehicles, off-tracking and steering, rollover prevention, skid control and jackknifing, doubles and triples, and antilock brakes. Required for Class A CDL applicants operating tractor-trailer combinations, especially relevant given Pennsylvania's mountainous terrain.

Testing Language

Pennsylvania administers CDL knowledge tests in both English and Spanish. This is a genuine distinction worth knowing, since several other states offer knowledge testing in English only.

Retest Rules

If you fail a knowledge test, you can retake it at a PennDOT Driver License Center. Retest wait times and fees can vary — confirm current specifics directly with your local Driver License Center before your retest attempt.

Practice All 3 Tests Free

500 real practice questions across General Knowledge, Air Brakes, and Combination Vehicles.

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Frequently Asked Questions

How many questions are on the General Knowledge test?

50 questions, 40 correct (80%) needed to pass. Required for every applicant.

How many questions are on the Air Brakes test?

25 questions, 20 correct needed. Skipping the air brake check on the skills test is an automatic fail.

How many questions are on the Combination Vehicles test?

20 questions, 16 correct needed. Required for Class A applicants.

What languages are the tests given in?

English and Spanish — a distinction from several other states.

What happens if I fail?

You can retake it at a Driver License Center — confirm current wait times and fees locally.

Sources: Pennsylvania Department of Transportation (PennDOT). Last verified July 2026.