Kentucky CDL Manual: Classes, Endorsements, and Study Tips

The Kentucky CDL manual is the official study guide published by the Kentucky Transportation Cabinet and the Kentucky State Police for anyone pursuing a commercial driver’s license in the state. You can download the current 2025 edition free as a PDF from the Transportation Cabinet’s website or the Kentucky State Police site.¹ Printed copies are available at any circuit court clerk’s office or regional driver licensing center. The PDF is searchable, which helps when you need to jump between air brakes, combination vehicles, or hazmat sections during study.

What the Manual Prepares You For

The manual is the source material for two separate tests Kentucky requires before issuing a CDL: a written knowledge exam and a three-part skills test. Both are administered by the Kentucky State Police.

The general knowledge exam has 50 questions covering vehicle operations, cargo handling, inspection procedures, and traffic laws. You need 80 percent to pass.² Depending on your license class and the endorsements you want, you may also sit for additional written tests:

Combination vehicles: 20 questions (required for Class A)
Air brakes: 25 questions (required if your vehicle has air brakes; failing it gets you the L restriction that bars you from driving air-brake vehicles)
Hazardous materials: 30 questions
Tanker, passenger, doubles/triples, school bus: 20 questions each

Fail the general knowledge test and you wait 24 hours to retake it, with no retest fee. Endorsement and specialty tests carry a $5 retest fee after the first failure. Pass your knowledge and vision tests and you’ll be issued a Commercial Learner’s Permit good for six months.² While you hold the CLP, a licensed CDL driver with the proper class and endorsements must sit in the front seat beside you whenever you operate a commercial vehicle on public roads.³

You must hold the CLP for at least 14 days before taking the skills test.⁴ Schedule the test by calling the Kentucky State Police at (800) 542-5990. You bring your own vehicle, along with a licensed CDL driver to accompany you to the testing site.⁵

The skills test has three scored parts:

Vehicle inspection. You walk around the vehicle and perform or explain a full pre-trip inspection covering the engine compartment, in-cab safety equipment and gauges, coupling system, brakes, tires, lights, and trailer components. The examiner scores each item you correctly identify and explain.⁶
Basic control skills. You maneuver through a cone course, performing exercises like straight-line backing, offset backing, and docking. Score depends on staying within boundaries and how many pull-ups you need.
Road test. You drive a route chosen by the examiner through intersections, highway ramps, railroad crossings, curves, and grades, scored at designated points on turns, merges, lane changes, speed control, signaling, and hazard awareness.

License Classes and Endorsements the Manual Covers

Kentucky issues commercial licenses in three classes based on vehicle size and configuration. Knowing which one you need tells you which sections of the manual matter most.

Class A: Any combination of vehicles with a gross combined weight rating of 26,001 pounds or more, provided the towed vehicle exceeds 10,000 pounds. Covers tractor-trailers, flatbeds, and most heavy hauling. A Class A holder can also drive Class B and Class C vehicles with the right endorsements.⁷
Class B: Any single vehicle of 26,001 pounds or more, or one towing a trailer that does not exceed 10,000 pounds. Dump trucks, large buses, box trucks. Class B holders can drive Class C vehicles with proper endorsements.⁷
Class C: Vehicles under 26,001 pounds that either carry 16 or more passengers (including the driver) or transport placarded hazardous materials.⁶

Endorsements expand what you can legally haul or operate. H covers hazardous materials, N covers tank vehicles, P covers passenger vehicles, S covers school buses (and requires the P endorsement too), T covers double and triple trailers, and X combines tank and hazmat. Each endorsement requires passing an additional knowledge test; the school bus and passenger endorsements also require a skills test. You can’t legally drive a vehicle requiring an endorsement unless it appears on your license.⁷

Restrictions work the other direction. The L restriction bars you from air-brake vehicles and lands on your license if you fail the air brake knowledge test or take your skills test in a vehicle without air brakes. Drivers under 21 receive a K restriction that prohibits interstate commerce.⁷

What the Manual Doesn’t Cover: Things You Still Need

Studying the manual gets you ready for the tests. It does not satisfy the other requirements Kentucky and federal law stack on top of the testing process. Before you can even sit for the written exam, you need to show up with the right documents and clearances in hand.

Documents at the Counter

Bring originals, not photocopies: a certified birth certificate for identity, your Social Security card with your current name, and two proofs of Kentucky residency dated within the past year. Residency documents include utility bills, bank statements, a lease, a mortgage statement, or a Kentucky voter registration card.⁸ Every CDL applicant, first-time or renewal, also undergoes a National Crime Information Center background check through the Kentucky State Police, which costs $3.¹

DOT Medical Certificate

Federal law requires every commercial driver to be medically certified before operating a commercial vehicle.⁹ The exam must be performed by a medical examiner on the FMCSA’s National Registry, not just any physician.¹⁰ A DOT physical typically costs between $60 and $125 depending on the provider. You’ll get a Medical Examiner’s Certificate (Form MCSA-5876); carry it on duty, and expect your permit application to stall without it.

Entry-Level Driver Training

Since February 2022, federal rules require every first-time CDL applicant to complete Entry-Level Driver Training before the skills test. The same requirement applies if you’re upgrading from Class B to Class A, or picking up a hazmat, passenger, or school bus endorsement for the first time.¹¹ ELDT has a theory portion (vehicle systems, pre-trip inspections, speed and space management, hazard perception, extreme driving conditions) requiring at least 80 percent on a written assessment, plus a behind-the-wheel portion in an actual commercial vehicle on public roads. Both must be completed through a provider listed on the FMCSA’s Training Provider Registry.¹² Your provider submits your certification to FMCSA by midnight of the second business day. Verify your record on the registry before your skills test; without the certification in the system, you won’t be allowed to test.

Age

You must be at least 18 for a Kentucky CDL. Drivers under 21 get the K restriction limiting them to intrastate commerce and are prohibited from operating school buses. Federal law requires age 21 to drive a commercial vehicle across state lines.⁷

Hazmat: An Extra Layer

If you want an H or X endorsement, passing the 30-question written test is only part of it. Federal law requires a TSA security threat assessment including fingerprinting and a criminal background check. TSA recommends starting at least 60 days before you need the endorsement.¹³ Kentucky residents schedule fingerprinting through the Kentucky State Police at (800) 542-5990. The fingerprint-based background check runs $138.25, which covers both the TSA’s $85.25 security threat assessment fee and additional state processing, with a separate $5 fee for the written hazmat test. At renewal, you retake the written hazmat test and the vision test unless it’s been less than two years since your last test.¹

Study Tips for the Kentucky CDL Exam

The manual runs over 100 pages, and the knowledge tests pull from every part of it. Skim the whole document first to understand the layout, then concentrate deep study on air brakes and pre-trip inspections. Those are the two areas where most first-time applicants fail, and both reward memorizing specific numbers: governor cut-out pressure (120–140 PSI), maximum air loss rates during the applied pressure test (3 PSI for a single vehicle, 4 PSI for a combination), low air warning activation (before 60 PSI), and spring brake engagement (20–40 PSI).

For the general knowledge test, pay close attention to stopping distances, right-of-way rules, and cargo securement. The questions aren’t tricky, but they reward precision. Knowing the answer is “four seconds” rather than “a safe distance” is what separates passing from retesting. The 80 percent threshold lets you miss about 10 questions on the general test, though comfortable passing comes from knowing the material rather than guessing on close calls.

The pre-trip inspection on the skills test is where most people lose points. Study the manual’s inspection section carefully: you need to name each component, describe what you’re checking for, and explain what a defect would look like. Vague answers cost you fast.

1
Kentucky Transportation Cabinet. Commercial Driver’s License
2
Kentucky State Police. Kentucky Commercial Driver’s License Manual
3
eCFR. 49 CFR 383.25 – Commercial Learner’s Permit
4
FindLaw. Kentucky Revised Statutes 281A.160 – Testing of Knowledge and Skills
5
Kentucky State Police. Drivers License Testing
6
Kentucky Transportation Cabinet. Kentucky Commercial Driver’s License Manual
7
Kentucky Legislative Research Commission. Kentucky Revised Statutes 281A.170 – Form of Licenses
8
Kentucky Transportation Cabinet. Valid Proof Documents for Kentucky Driver’s Licenses, Permits, and Identification Cards
9
eCFR. 49 CFR 391.41 – Physical Qualifications for Drivers
10
FMCSA National Registry. Welcome to the National Registry of Certified Medical Examiners
11
eCFR. 49 CFR Part 380 – Special Training Requirements
12
Federal Motor Carrier Safety Administration. Training Provider Registry
13
Transportation Security Administration. HAZMAT Endorsement