Tanker endorsement practice test

Free tanker practice questions

Ten questions from the PassRig bank. Pick an answer in your head, then show the answer to read why. The full bank, timed mock exams and AI explanations live in the app.

1. Tank vehicles are harder to drive than other trucks mainly because of:

   • ATheir low center of gravity
   • BTheir high center of gravity and the movement of the liquid
   • CTheir short wheelbase
   • DTheir lack of brakes on the trailer
   Show answer

   Answer: B. Their high center of gravity and the movement of the liquid

   The load sits high, so the tank tips easily, and liquid moves inside it. Many tanker rollovers happen on curves at speeds below the posted limit, so slow down well before every curve and ramp.

   Source: FMCSA CDL Manual, Section 8.3 (Safe Driving: High Center of Gravity)

2. Bulkheads divide a tank into separate compartments. When loading a tank with bulkheads you must pay attention to:

   • AThe color of the liquid
   • BWeight distribution across the compartments
   • CThe brand of the liquid
   • DThe time of day
   Show answer

   Answer: B. Weight distribution across the compartments

   Putting too much in the front or rear compartments overloads an axle. Spread the load so each axle stays within its limit and the vehicle handles evenly.

   Source: FMCSA CDL Manual, Section 8.2 (Bulkheads)

3. If the drive wheels or trailer wheels start to skid in a tank vehicle, you should:

   • ABrake harder
   • BRelease the brakes to get traction back
   • CPull the trailer hand valve
   • DAccelerate
   Show answer

   Answer: B. Release the brakes to get traction back

   A skidding wheel has no grip and cannot steer or stop you. Let off the brakes so the wheels roll and regain traction, then steer. A tank vehicle that jackknifes is very likely to roll.

   Source: FMCSA CDL Manual, Section 8.3 (Skids)

4. Before driving a tank vehicle, you should know where the emergency shut-off controls are because:

   • AThe inspector asks about them
   • BYou may need to stop a leak or fire quickly
   • CThey control the speed
   • DThey release the parking brake
   Show answer

   Answer: B. You may need to stop a leak or fire quickly

   Tank vehicles have internal and external shut-off valves. In an emergency you must be able to close them fast. Find them during the pre-trip inspection, not during the emergency.

   Source: FMCSA CDL Manual, Section 8.1.3 (Special Purpose Equipment)

5. Before loading, unloading or driving, the intake, discharge and cut-off valves must be:

   • ARemoved for cleaning
   • BAll fully open
   • CTaped shut
   • DIn the correct position for what you are about to do
   Show answer

   Answer: D. In the correct position for what you are about to do

   You must know which valve is which and set each one correctly. A valve left open can dump the load; a valve left closed can over-pressure the tank or stop the transfer.

   Source: FMCSA CDL Manual, Section 8.1 (Inspecting Tank Vehicles: Valves)

6. The emergency equipment you must carry on a tank vehicle:

   • ADepends on the product you carry, so you must know what is required and make sure it is on board and working
   • BIs the same for every tank vehicle
   • CIs only a fire extinguisher
   • DIs optional for food-grade loads
   Show answer

   Answer: A. Depends on the product you carry, so you must know what is required and make sure it is on board and working

   Different products call for different equipment, from fire extinguishers to protective gear. Find out what your load requires and check it as part of the inspection.

   Source: FMCSA CDL Manual, Section 8.1 (Inspecting Tank Vehicles: Emergency Equipment)

7. Smooth bore (unbaffled) tanks are usually used to carry:

   • AGasoline
   • BCompressed gases
   • CDry cement
   • DFood products such as milk
   Show answer

   Answer: D. Food products such as milk

   Sanitation 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)

8. You should never load a cargo tank completely full because:

   • AA full tank surges more than a partly full one
   • BFull tanks are illegal on interstate highways
   • CLiquids expand as they warm and need room, or the tank can leak or burst
   • DThe pump cannot fill the last few gallons
   Show answer

   Answer: C. Liquids expand as they warm and need room, or the tank can leak or burst

   A tank with no outage has nowhere for the liquid to go when it expands. Leaving the required outage protects the tank, the load and everyone nearby.

   Source: FMCSA CDL Manual, Section 8.2.6 (Outage)

9. If you must stop quickly in a tank vehicle to avoid a crash, you should:

   • AUse controlled or stab braking and avoid steering sharply while braking
   • BLock the brakes and hold them
   • CSteer hard onto the shoulder while braking
   • DUse the trailer hand valve only
   Show answer

   Answer: A. Use controlled or stab braking and avoid steering sharply while braking

   Controlled or stab braking keeps the wheels from locking. Remember that a sharp steer while braking hard can roll a tanker over.

   Source: FMCSA CDL Manual, Section 8.3.2 (Controlling Surge)

10. Skids in tank vehicles are usually caused by:

    • ADriving with the required outage
    • BCarrying a baffled tank
    • CDriving during daylight
    • DOver-steering, over-accelerating or over-braking
    Show answer

    Answer: D. Over-steering, over-accelerating or over-braking

    Any input that asks for more traction than the road can give starts a skid. Drive smoothly to avoid them, and if the wheels do skid, release the brakes to regain traction.

    Source: FMCSA CDL Manual, Section 8.3.5 (Skids)