Free practice test
CDL Tanker practice test
The free test below follows the real Tanker test: 20 questions, 16 right to pass, 20 to 25 minutes. The ideas are simple, but the test checks that you understand how a moving liquid changes the way a truck handles.
FirstTry CDL is not affiliated with any DMV, FMCSA or government agency. Practice questions are exam-style questions built from the official CDL manual, not actual test questions.
How the Tanker test is scored
You need 16 of 20 right, which is 80%. That means you can miss 4. Drivers who want the N endorsement to haul liquids or gases in a tank. Add the Hazmat test and you can earn the X endorsement.
What is on the Tanker test
- Liquid surge and why it matters when you brake or turn
- Baffles, bulkheads and smooth bore tanks
- Outage: leaving room for the liquid to expand
- Inspecting a tank vehicle: leaks, valves, vents and manhole covers
- Safe driving: high center of gravity, curves and stopping distance
- Loading and unloading rules
What trips drivers up
Surge
When you brake, the liquid pushes forward. In a partly full tank, that push can move the truck.
Baffles and smooth bore tanks
Baffles have holes that slow the surge front to back. A smooth bore tank has no baffles inside, so the surge can be strong.
Outage
Liquids expand as they warm, so never fill a tank to the top. How much room to leave depends on the product.
High center of gravity
A liquid load rides high, so rollover risk is greater. Take curves well below the posted speed.
Numbers come from the CDL manual and federal rules. A few differ by state or manual edition, so check your own state's manual. See our sources.
More practice tests
Common questions
How many questions are on the CDL Tanker test?
The national default is 20 questions, and you need 16 right (80%) to pass.
What is liquid surge?
It is the movement of liquid inside a tank when you speed up, brake or turn. It can push the truck in ways you do not expect.
What is the difference between a baffle and a bulkhead?
A bulkhead divides the tank into compartments, and the liquid cannot pass between them. A baffle has holes in it and only slows the liquid down.
Is there a skills test for the tanker endorsement?
No separate one. You pass the knowledge test and do your skills test in a tank vehicle if your state requires it. Check your state's rules.