commercial exam
CDL (Commercial Driver License) study guides
The U.S. Commercial Driver License qualifies professional drivers for Class A, B, and C trucks plus passenger and hazardous endorsements.
Topics (25)
Air Brakes
18% of testAir-brake endorsement covers the components, leak tests, slack adjusters, and emergency procedures for trucks fitted with air-brake systems.
Hazmat (HazMat Endorsement)
12% of testThe H endorsement authorises the transport of hazardous materials in placardable amounts and requires a TSA security threat assessment.
School Bus (S Endorsement)
8% of testThe S endorsement covers loading, unloading, evacuation, and danger-zone operations for school-bus drivers transporting students.
Passenger (P Endorsement)
7% of testThe P endorsement is required for any commercial vehicle designed to transport 16 or more passengers including the driver.
Doubles / Triples (T Endorsement)
6% of testThe T endorsement authorises pulling more than one trailer — most often two pup trailers behind a truck-tractor.
Tankers (N Endorsement)
7% of testThe N endorsement covers liquid-cargo handling, surge dynamics, baffles, and unloading procedures for tank trucks.
Combination Vehicles
10% of testCombination-vehicle theory covers fifth-wheel coupling, kingpin/locking-jaw inspection, off-tracking, and air-line connections.
Pre-Trip Inspection
15% of testThe pre-trip vehicle inspection is the most-failed CDL skills test segment. Candidates must verbally identify and inspect 100+ items in the correct order.
Basic Controls (Maneuvers)
10% of testBasic-controls testing covers off-set alley dock, parallel park, straight-line backing, and right-side parallel — the maneuvering portion of the CDL skills test.
On-Road Driving Test
15% of testThe on-road test puts you in real traffic for 30–60 minutes — the examiner scores lane control, intersection handling, hill starts, and railroad-crossing procedure.
General Knowledge
20% of testThe General Knowledge test (50 multiple-choice questions) is required for every CDL class and covers vehicle systems, road rules, and emergency procedures.
Shifting & Transmission
5% of testShifting covers manual transmissions (typically 9- to 18-speed), double-clutching, range and splitter operation, and downshifting on grades.
Cargo Securement
4% of testCargo securement covers tie-downs, working load limits, blocking and bracing, and DOT inspection criteria for various cargo classes.
Logbook & ELD (Hours of Service)
5% of testHours-of-service rules limit driving to 11 hours within a 14-hour duty window after 10 hours off; ELDs (Electronic Logging Devices) automate enforcement.
DOT Medical Card
2% of testFederal CDL operators must hold a valid DOT medical examiner's certificate (medical card), renewed every 1–2 years.
Entry-Level Driver Training (ELDT)
5% of testFMCSA Entry-Level Driver Training (ELDT) is a federal pre-CDL training requirement that all first-time Class A/B applicants must complete at a TPR-registered school.
Air Brake Restriction (L/Z) Removal
4% of testThe L (no-air-brakes) and Z (no-full-air-brakes) restrictions appear on a CDL when the applicant tests in a vehicle without air brakes; removing them requires a separate skills test.
Class A vs. Class B (License Class Selection)
5% of testClass 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.
ELD & Hours-of-Service (HOS) Compliance
6% of testElectronic Logging Devices (ELDs) are required for most interstate CMV drivers; HOS rules cap driving and on-duty time to reduce fatigue-related crashes.
Pre-Employment Screening & Drug/Alcohol Testing
4% of testFMCSA Drug & Alcohol Clearinghouse, DOT pre-employment drug screen, and PSP record review are required before a carrier can place a CDL holder behind the wheel.
CDL Learner Permit (CLP)
4% of testThe Commercial Learner Permit (CLP) authorizes practice driving with a qualified CDL holder before sitting the skills test. Federal law requires holding the CLP for at least 14 days.
Cargo Securement Standards
6% of testFMCSA cargo-securement rules dictate working load limits, tiedown counts, and commodity-specific rules for logs, vehicles, large objects, and dressed lumber.
State-Specific CDL Variations
4% of testWhile 49 CFR Part 383 sets minimum federal CDL standards, individual states add variations: skills-test layouts, intrastate-only restrictions (E/V), and 18 vs. 21 minimum age rules.
Medical Card Self-Certification
3% of testCDL holders must self-certify their type of operation (interstate excepted, interstate non-excepted, intrastate excepted, or intrastate non-excepted) and maintain a valid DOT medical card on file.
Roadside Inspection & CSA Score
5% of testCSA (Compliance, Safety, Accountability) tracks driver and carrier safety performance. Roadside inspection violations affect both the driver Pre-Employment Screening Program (PSP) record and the carrier Safety Measurement System (SMS) score.
Locale-specific guides
Every CDL topic is published with locale-specific framing for candidates testing in different countries. Pass-rate stats, regulatory context, and study tips all change by locale.
- United StatesAmerican candidates
- United KingdomBritish candidates
- IndiaIndian candidates
- PhilippinesFilipino candidates
- NigeriaNigerian candidates
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Air-brakes, hazmat, pre-trip — every endorsement, every state. Built with a Pass Guarantee.