Tanker endorsement practice test
The tank vehicles test earns the N endorsement. It is short but specific: how liquid surge moves a truck, why outage and the baffles matter, and how to brake and take curves with a sloshing load. The sample questions below come from Section 8 of the FMCSA CDL manual.
- 20questions on the real test
- 80%pass mark, 16 correct answers
- 40questions in the PassRig bank
- S8of the FMCSA CDL manual
Free tanker practice quiz
Ten questions from the PassRig bank. Tap an answer to lock it in and read why it is right, with the manual section it comes from. The score keeps count; 80% is the pass mark. The full bank, timed mock exams and mistake review live in the app.
0 of 10 right0 of 10 answered
Tank vehicles are harder to drive than other trucks mainly because of:
Answer: B. Their high center of gravity and the movement of the liquidHauling liquids in tanks takes special skill because of the high center of gravity and the movement of the liquid. Much of the load's weight is carried high off the road, which makes the vehicle top-heavy and easy to roll over, and the surge of the liquid changes how the vehicle handles.
Source: FMCSA CDL Manual, Section 8.2 (Driving Tank Vehicles)
Bulkheads divide a tank into separate compartments. When loading a tank with bulkheads you must pay attention to:
Answer: B. Weight distribution across the compartmentsSome liquid tanks are divided into several smaller tanks by bulkheads. When loading and unloading these smaller tanks, pay attention to weight distribution and do not put too much weight on the front or rear of the vehicle.
Source: FMCSA CDL Manual, Section 8.2.3 (Bulkheads)
If the drive wheels or trailer wheels start to skid in a tank vehicle, you should:
Answer: B. Take action to restore traction to the wheels, such as releasing the brakesOn tank trailers, if your drive or trailer wheels begin to skid, your vehicle may jackknife. When any vehicle starts to skid you must take action to restore traction to the wheels. In a braking skid that means stop braking so the wheels roll again; in an acceleration skid, take your foot off the accelerator.
Source: FMCSA CDL Manual, Section 8.3.5 (Skids)
You must never drive a tank vehicle with:
Answer: B. Open valves or manhole coversNever drive a tank vehicle with open valves or manhole covers. Before loading, unloading or moving the vehicle make sure the valves are in the correct position, and make sure the manhole covers have gaskets and close correctly.
Source: FMCSA CDL Manual, Section 8.1.2 (Check Special Purpose Equipment)
Before loading, unloading or driving, the intake, discharge and cut-off valves must be:
Answer: D. In the correct position for what you are about to doCheck the intake, discharge and cut-off valves and make sure they are in the correct position before loading, unloading or moving the vehicle. Never drive a tank vehicle with open valves or manhole covers.
Source: FMCSA CDL Manual, Section 8.1.1 (Leaks)
The emergency equipment you must carry on a tank vehicle:
Answer: A. Depends on your vehicle, so you must find out what is required and make sure you have it and it worksCheck the emergency equipment required for your vehicle. Find out what equipment you are required to carry and make sure you have it and that it works.
Source: FMCSA CDL Manual, Section 8.1.3 (Special Equipment)
Smooth bore (unbaffled) tanks are usually used to carry:
Answer: D. Food products such as milkSanitation rules make baffled tanks hard to clean, so food-grade liquids ride in smooth tanks with nothing inside to slow the surge.
Source: FMCSA CDL Manual, Section 8.2.5 (Unbaffled Tanks)
You should never load a cargo tank completely full because:
Answer: C. Liquids expand as they warm and you must leave room for the expanding liquidNever load a cargo tank totally full. Liquids expand as they warm, and the room you leave for the expanding liquid is called outage. Different liquids expand by different amounts, so you must know the outage requirement for the liquid you haul.
Source: FMCSA CDL Manual, Section 8.2.6 (Outage)
If you must stop quickly in a tank vehicle to avoid a crash, you should:
Answer: A. Use controlled or stab braking and avoid steering sharply while brakingControlled braking means applying the brakes as hard as you can without locking the wheels. Stab braking means braking fully, releasing when the wheels lock, and reapplying once they roll again (only on vehicles without ABS). Both keep the vehicle in a straight line. If you steer quickly while braking, your vehicle may roll over.
Source: FMCSA CDL Manual, Section 8.3.2 (Controlling Surge)
Skids in tank vehicles are usually caused by:
Answer: D. Over-steering, over-accelerating or over-brakingDo not over steer, over accelerate or over brake, or your vehicle may skid. On tank trailers a drive wheel or trailer wheel skid may lead to a jackknife. When any vehicle starts to skid, take action to restore traction to the wheels.
Source: FMCSA CDL Manual, Section 8.3.5 (Skids)
What the tanker test covers
- Inspecting tank vehicles: leaks, valves and manhole covers
- Liquid surge and how it affects stopping and curves
- Baffled, unbaffled and bulkhead tanks
- Outage and how full to load a tank
- Safe driving rules for tankers
Who needs it
Drivers who will haul liquids or gases in bulk tanks. Pair it with hazmat for the X endorsement.
The test has 20 multiple-choice questions and the passing score is 80%, so you can miss 4. Your state DMV or DOT administers it; the federal rules are on the FMCSA CDL page. Study Section 8 of the CDL manual alongside these questions.
More CDL practice tests
Guides for this test
Tanker test questions
How many questions are on the tanker endorsement test?
20 questions. 16 correct answers reach the 80% pass mark.
What is the X endorsement?
X is tanker plus hazmat combined. You pass both knowledge tests, and the hazmat side also needs the TSA background check.
Why is liquid surge such a big deal on the tanker test?
Because it is the thing that rolls tankers over. Surge pushes the truck forward after you stop and sideways in curves, so the test checks that you know to slow early and brake gently.