Free Pennsylvania DMV CDL — General Knowledge Practice Test 2026
The Pennsylvania CDL — General Knowledge knowledge test has ~50 questions, and you need ~40 correct (80%) to pass. Practice free with questions written from the official Pennsylvania driver handbook — every one has a clear explanation, and you can retake as often as you like with no sign-up.
Content reviewed against official driver handbooks · August 12, 2026
What's on the Pennsylvania written test
The Pennsylvania CDL — General Knowledge knowledge test has ~50 questions; you need ~40 correct (80%) to pass.
Based on the official Pennsylvania exam format — always confirm current details with your state DMV.
Practice by topic
Focus on one area at a time — each topic has its own set of Pennsylvania practice questions.
Learn the shapes, colors, and meanings of regulatory, warning, and guide signs — from stop and yield to construction and school-zone signs.
Speed limits, turning and signaling rules, headlight and seat-belt requirements, and the everyday laws every driver must follow.
How to read traffic signals, lane lines, and pavement markings — including yellow and white lines, arrows, and flashing lights.
Who goes first at intersections, four-way stops, roundabouts, and crosswalks, and how to yield to pedestrians and emergency vehicles.
Following distance, scanning, blind spots, using your lights, and the habits that prevent crashes and keep you in control.
Driving safely around motorcycles, bicycles, large trucks, pedestrians, and school buses — and knowing who has the right of way.
Blood alcohol limits, zero-tolerance and implied-consent laws, and how alcohol and drugs — legal or not — affect your driving.
Legal and illegal parking, colored curbs, distances from hydrants and crossings, and how to park safely on hills.
Choosing a safe speed, keeping a space cushion, adjusting for weather and traffic, and understanding stopping distance.
What to do when things go wrong — brake failure, tire blowouts, skids, and stalling on railroad tracks.
The point system, license suspension, provisional-license rules, insurance requirements, and other licensing basics.
How to pass the first time
- Read the official Pennsylvania driver handbook at least once before test day.
- Practice by topic to find your weak spots, then fix them.
- Take full-length practice tests until you pass comfortably every time.
- Read every explanation — understanding beats memorizing.
Pennsylvania CDL — General Knowledge test — frequently asked questions
How many questions are on the Pennsylvania CDL — General Knowledge test?
The Pennsylvania CDL — General Knowledge knowledge test has ~50 questions, and you need ~40 correct (80%) to pass. Our practice tests mirror that format.
How many questions can I miss on the Pennsylvania CDL — General Knowledge test?
You can miss up to ~10 of the ~50 questions and still pass — you need ~40 correct, which is 80%.
Can I retake the practice test?
Yes — practice as often as you like, completely free. The questions and answer choices are shuffled each time.
Can I take the Pennsylvania practice test in Spanish?
Yes. Every question here is available in English and Spanish — switch languages anytime. Many states also offer the real knowledge test in languages other than English; confirm what Pennsylvania offers with your DMV.
Can I practice on my phone?
Yes. The practice tests work in any mobile or desktop browser — no app or sign-up needed — so you can study anywhere.
Are these the real DMV test questions?
No. Our questions are original, written from the current official Pennsylvania driver handbook to match the real test's topics and style. We are not affiliated with any DMV or government agency.
What's the best way to study?
Read the Pennsylvania driver handbook, practice by topic to target weak areas, and finish with full-length tests until you consistently pass.
Other Pennsylvania practice tests
Take the CDL — General Knowledge test in another state
Every Pennsylvania question is written from the official Pennsylvania 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
Pennsylvania CDL — General Knowledge questions with answers
20 sample questions from the Pennsylvania CDL — General Knowledge question bank — each with the correct answer, a short explanation, and the section of the official handbook it comes from.
Show all 20 questions with answers
1. Which abilities does alcohol impair, affecting safe driving?
Correct answer: Reaction time, depth perception, night vision, and coordination
Drinking degrades your reaction time, depth perception, night vision, and muscle coordination, and it dulls the brain areas that govern judgment.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Alcohol and Driving)
2. How often must the hazardous materials endorsement be recertified?
Correct answer: Every four years
Every four years you have to recertify the hazmat endorsement by retaking the HAZMAT knowledge test and clearing the security threat assessment.
Source: Pennsylvania CDL Manual — Section 1: Introduction (Commercial Driver License Tests)
3. Whenever you must run your windshield wipers, what else are you required to do?
Correct answer: Turn on your headlights
Any time the windshield wipers are running, the law requires your headlights to be on so others can see you.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (When It Is Hard to See)
4. What is the single most important reason for inspecting your commercial vehicle?
Correct answer: Safety — protecting yourself and everyone else on the road
Safety is the most important reason to inspect — for yourself and other road users; a defect found in advance can prevent a breakdown or crash.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Why Inspect)
5. At a railroad crossing with gates and flashing lights, when may you cross the tracks?
Correct answer: Once the gates have raised and the lights stop flashing
You must stay stopped until the gates go back up and the lights stop flashing, then proceed only when it is safe.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Warning Signs and Devices)
6. Total stopping distance is the sum of which three distances?
Correct answer: Perception distance, reaction distance, and braking distance
Total stopping distance equals perception distance plus reaction distance plus braking distance.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Stopping Distance)
7. Under the property-carrying hours-of-service rules, what is the maximum number of hours you may drive after 10 consecutive hours off duty?
Correct answer: 11 hours
After 10 straight hours off duty, a property-carrying driver is limited to no more than 11 hours behind the wheel.
Source: Pennsylvania CDL Manual — Section 1: Introduction (Hours of Service Regulations)
8. If a front tire suddenly fails, what is the most important immediate action?
Correct answer: Grip the steering wheel firmly with both hands
Keep both hands gripping the wheel tightly, since a blown front tire can wrench it from your hands; keep off the brake until the truck slows on its own.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Respond to Tire Failure)
9. Why should you watch carefully for drivers of vans, loaded station wagons, and rental trucks?
Correct answer: Their blocked vision means they may not see you
Drivers whose vision is blocked are a dangerous hazard; rental-truck drivers in particular are often unused to their limited side and rear vision.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Drivers Who Are Hazards)
10. When passing a bicyclist on the roadway, how much space must you allow between your vehicle and the bicycle?
Correct answer: At least four feet
When passing, keep a gap of at least four feet separating your vehicle from the bicycle.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Drivers Who Are Hazards)
11. A person attending a parked placarded vehicle must remain in the vehicle or within what distance of it?
Correct answer: Within 100 feet, with the vehicle in clear view
Whoever attends the vehicle has to stay inside it — awake, and not in the sleeper — or remain within 100 feet while keeping it in clear view.
Source: Pennsylvania CDL Manual — Section 9: Hazardous Materials (Attending Parked Vehicles)
12. At what point does alcohol begin to impair a driver?
Correct answer: With the very first drink
Impairment begins with the first drink; all drivers are affected by drinking alcohol.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Alcohol and Driving)
13. When driving on a commercial learner's permit, who is required to ride with you?
Correct answer: A CDL holder for that vehicle type, at least 21, seated beside you
Someone holding a valid CDL for that class of vehicle must ride in the seat next to you, and that person has to be 21 or older.
Source: Pennsylvania CDL Manual — Section 1: Introduction (Applying for a PA CDL)
14. At night, within what distance of an oncoming vehicle must you dim your high beams?
Correct answer: Within 500 feet
Lower your high beams once you come within 500 feet of a vehicle approaching you, and likewise when trailing another vehicle by less than 500 feet.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Night Driving Procedures)
15. If you notice signs of fatigue while driving, what is the only safe cure?
Correct answer: Stopping and getting sleep
The only safe cure for drowsiness is to stop and sleep; coffee or fresh air will not make a tired driver alert.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Night Driving and Driver Fatigue)
16. A red triangle with an orange center displayed on the back of a vehicle warns you that the vehicle is what?
Correct answer: Traveling much slower than the normal flow of traffic
The slow-moving vehicle emblem — a red triangle with an orange center — identifies vehicles such as farm machinery or tractors that travel far below normal traffic speed.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Drivers Who Are Hazards)
17. About how much should you reduce speed on a road packed with snow?
Correct answer: By about one-half
On packed snow, reduce your speed by about half; on a wet road reduce by about a third, and on ice slow to a crawl.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Matching Speed to the Road Surface)
18. What do the federal rules say about text messaging while driving a commercial motor vehicle?
Correct answer: It is prohibited while driving
Texting — manually entering or reading text on a device — is prohibited while driving a CMV, and repeat convictions lead to disqualification.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Texting)
19. To recover from a trailer skid (jackknife), what should you do with the brakes?
Correct answer: Release the service brakes to regain traction
Let off the service brakes to recover traction, and do not reach for the trailer hand brake — braking those trailer wheels is what started the skid.
Source: Pennsylvania CDL Manual — Section 6: Combination Vehicles (Prevent Trailer Skids)
20. If another vehicle is tailgating you, what is a safe way to reduce the risk of a crash?
Correct answer: Increase your following distance in front of you
Open up the room in front of you by increasing your following distance, so you can avoid sudden speed or direction changes and let the tailgater pass.
Source: Pennsylvania CDL Manual — Section 2: Driving Safely (Dealing with Tailgaters Safely)