CDL Tanker Practice Test 2026: Sample Questions and Answers
By Rish P · November 11, 2026 · Updated September 10, 2026
The CDL tanker (N) endorsement test covers the unique handling of tank vehicles, and it is usually about 20 questions with an 80% passing score. Because the tanker endorsement is not part of the ELDT rule, you only need to study and pass this knowledge test, no formal training is required.
What the test covers
The tanker test focuses on what makes hauling liquids different: liquid surge and how it pushes the vehicle, the high center of gravity that increases rollover risk, smooth braking and cornering, tank inspection, baffled versus unbaffled tanks, and outage, the space left for the liquid to expand.
Sample questions
- Liquid surge is:
- a) The sound the engine makes
- b) Liquid moving back and forth in a partially filled tank, pushing the vehicle
- c) A braking system
- d) A type of trailer
- Compared with other trucks, tankers have a higher risk of:
- a) Flat tires
- b) Rollover, due to a high center of gravity
- c) Engine failure
- d) Low fuel
- Baffles in a tank help to:
- a) Increase speed
- b) Control the forward-and-back surge of the liquid
- c) Add weight
- d) Cool the load
- "Outage" refers to:
- a) A power failure
- b) The empty space left so the liquid can expand with temperature
- c) An unpaid bill
- d) A missed exit
Answers: 1) b. 2) b. 3) b. 4) b.
How to pass
Study the tank vehicles section of your CDL manual, paying special attention to surge, rollover risk, and outage, then take practice tests until you are steadily above 80%. Since there is no ELDT requirement for tanker, the knowledge test is the only real hurdle.
The bottom line
The tanker test is short and training-free: about 20 questions, 80% to pass, no ELDT. Master liquid surge and rollover prevention, and you are ready to add one of the most in-demand endorsements, especially when paired with hazmat.
Frequently asked questions
How many questions are on the tanker test?
Most states use about 20 multiple-choice questions on tank vehicles, with an 80% passing score. The exact count varies by state.
Does the tanker test require training first?
No. The tanker endorsement is not covered by the ELDT rule, so you only need to study and pass the knowledge test, no formal training required.
What is the most tested tanker concept?
Liquid surge, how liquid moving in a partially filled tank affects vehicle control, and the high center of gravity that raises rollover risk.
What is 'outage' on a tanker?
Outage is the space left in a tank to allow the liquid to expand with temperature. You must not overfill; the amount of outage depends on the liquid.
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