What the Alabama CDL Permit Test Covers
The Alabama CDL knowledge test is 50 multiple choice questions drawn from the official Alabama CDL Manual. You need to answer at least 40 correctly — an 80% passing score — to receive your Commercial Learner's Permit (CLP).
The test is not timed, costs $5 per attempt, and is taken in person at an ALEA Driver License office. You can retake it the same day if you don't pass. Most people who fail do so not because the material is hard, but because they studied the right topics the wrong way — reading without testing themselves.
Quick Facts
50 questions • 80% to pass (40 correct) • $5 per attempt • Not timed • Computer-based at ALEA • No mandatory waiting period between retakes
The Highest-Priority Topics to Study
Not all sections of the CDL manual carry equal weight on the exam. Based on the structure of the test, focus the majority of your study time on these four areas first:
1. Driving Safely (Section 2) — Highest Priority
The largest section and the most heavily tested. Covers following distance (1 second per 10 feet of vehicle length under 40 mph, add 1 second over 40 mph), stopping distances (approximately 300 feet at 55 mph), mirror checks (every 5–8 seconds), skid control, adverse weather driving, and right-turn technique. Know the numbers cold.
2. Pre-Trip Vehicle Inspection (Section 4) — High Priority
Tested on both the knowledge test and the skills test. Know the 7-step inspection process, minimum tread depths (4/32 inch on steering axles, 2/32 inch on all others), maximum steering wheel play (2 inches on a 20-inch wheel), and what constitutes an automatic failure during the skills test inspection.
3. Air Brakes (Sections 10–11) — High Priority
Multiple specific numbers the exam tests repeatedly: normal operating pressure 100–125 psi, low air warning at 60 psi, spring brakes activate between 20–45 psi, air leakage rate for a single vehicle no more than 3 psi per minute with brakes released. Know all four parts of the air brake check or it's an automatic failure on the skills test.
4. Alcohol and Hours of Service (Section 12) — High Priority
Zero-tolerance questions that appear on every exam. BAC limit in a CMV is 0.04% (not the regular 0.08%). HOS daily driving limit is 11 hours. On-duty window is 14 hours. Required break after 8 cumulative hours of driving is 30 minutes. Required reset is 10 consecutive off-duty hours.
Key Numbers to Memorize Before Test Day
| Rule | Number |
|---|---|
| Passing score | 80% — 40 of 50 correct |
| BAC limit in a CMV | 0.04% |
| Normal air brake pressure | 100–125 psi |
| Low air warning activates | ~60 psi |
| Spring brakes activate | 20–45 psi |
| Daily driving limit (HOS) | 11 hours |
| On-duty window | 14 consecutive hours |
| Break after 8 hrs driving | 30 minutes |
| Required reset (off-duty) | 10 consecutive hours |
| Max gross vehicle weight | 80,000 lbs |
| Stopping distance at 55 mph | ~300 feet |
| Following distance under 40 mph | 1 sec per 10 ft |
| Front axle tread depth minimum | 4/32 inch |
| All other axle tread depth | 2/32 inch |
How to Study for the Alabama CDL Permit Test
Step 1: Read the Official Manual Once
Download the free Alabama CDL Manual from alea.gov and read it cover to cover — especially Sections 1 through 12. Don't try to memorize on this pass. Just build familiarity with the topics and structure.
Step 2: Use This Study Guide by Section
Go back through the manual section by section using our interactive CDL study guide — it breaks down every section with the key rules and numbers highlighted, so you know exactly what to focus on.
Step 3: Take Practice Tests Daily
Take our free 40-question practice test every day for a week. Each session randomizes the questions so you can't memorize order. Track which topics you consistently miss and go back to those sections in the manual.
Step 4: Get the Full 150-Question Practice Book
Our complete practice test book has 150 original questions across all tested topic areas — with full explanations in the answer key so you understand the rule, not just the right letter. Available as an instant PDF download for $12.
Step 5: Score 90%+ Before Booking Your Appointment
The real test requires 80%. Aim for 90%+ consistently on practice questions before scheduling your ALEA appointment. The extra margin protects you against unfamiliar question phrasing on the actual exam.
The Most Common Reason People Fail
People who fail the CDL permit test almost always made the same mistake: they read the manual without testing themselves. Reading feels productive but doesn't reveal your blind spots. Practice tests do. Use the free test on this site daily — it's the most effective study method.