Louisiana CDL Practice Test 2026

Free Louisiana CDL practice test: General Knowledge, Air Brakes and Combination Vehicles questions written from the official CDL manuals, each with an explanation.

The three knowledge tests

Practice questions

20 questions, answered right here. Tap an option to see why.

0 of 20 answeredScore: 0/2016 to pass
  1. 1.

    A driver hauls a full load out in the morning and drives the same route back with an empty trailer. What should the driver expect on the return trip?

  2. 2.

    You are hauling a tarped load down the highway. Why should you keep glancing at the cover in your mirrors?

  3. 3.

    A tractor's FMVSS certification label shows no gross combination weight rating. How is the GCWR of the tractor-trailer then established?

  4. 4.

    In defensive driving, what does the word hazard refer to?

  5. 5.

    An oncoming driver leaves their high beams on and the glare is hurting your vision. What should you do?

  6. 6.

    After signalling, why should a lane change be made slowly and smoothly?

  7. 7.

    Your trailer sits visibly lower on the right side because the freight has settled against that wall. Gross and axle weights are all legal. What is the safety problem?

  8. 8.

    Two hours into a long run you stop for a meal break, then continue. When is your next required cargo check?

  9. 9.

    Where is the ABS malfunction lamp on a trailer?

  10. 10.

    Which gear and what speed should you use when backing a heavy vehicle?

  11. 11.

    How should your hands be placed on the steering wheel of a commercial vehicle?

  12. 12.

    You wear prescription lenses and own a tinted pair that helps with daytime glare. Should you wear them for night driving?

  13. 13.

    Adding perception, reaction and braking together, the minimum total stopping distance at 55 mph is about:

  14. 14.

    The safety relief valve on the supply tank lets air escape. This means:

  15. 15.

    Why does an overheated brake drum reduce braking force even before the lining material has worn out?

  16. 16.

    Before you back under a trailer, the fifth wheel should be:

  17. 17.

    Missing leaves in a leaf spring is a suspension defect. At what point does it put the vehicle out of service?

  18. 18.

    What is a simple way to check whether the road surface is beginning to ice up?

  19. 19.

    Under the federal prohibition on texting by CMV drivers, what does texting cover?

  20. 20.

    You are running empty on a windy day and are about to exit a long tunnel. What should you expect?

Questions people ask

How do I get a CDL in Louisiana?
Pass the written knowledge tests for the class and endorsements you want, hold a commercial learner's permit for at least 14 days, complete federal Entry-Level Driver Training, then pass the skills test. Louisiana's licensing agency publishes the current fees and appointment rules.
How many questions are on the Louisiana CDL General Knowledge test?
50, with 80% correct to pass. Air Brakes adds 25 questions and Combination Vehicles 20.
Are CDL rules the same in every state?
The core knowledge is federal — 49 CFR and the AAMVA model manual — so the questions barely change across state lines. Fees, waiting periods and endorsement details are set by the state.

CDL practice by state

Where this comes from

Independent study aid. Not affiliated with, endorsed by or connected to any Department of Motor Vehicles or government agency. Questions are written from the official handbooks listed above; no exam result is guaranteed.