CDL Endorsements

CDL Endorsements Tank Vehicles Practice Questions

Tank Vehicles makes up 8 of every 50 questions on a Tigertest CDL Endorsements practice test. Here are 10 of the 32 questions on it, each with the answer and the reason.

Updated 2026-11-10 by the Tigertest team. Based on FMCSA CDL Manual sections 4, 5, 6, 8 and 9. HazMat also needs a TSA security threat assessment.

1. 1. A CDL driver needs the tank endorsement to haul liquids in tanks with an aggregate rated capacity of at least how many gallons?

   • A.10,000 gallons
   • B.1,000 gallons
   • C.500 gallons
   • D.2,500 gallons

   Answer: B. A tank vehicle carries liquid or gaseous materials in tanks with an aggregate rated capacity of 1,000 gallons or more (49 CFR 383.5). 500 gallons is below the threshold, and 2,500 or 10,000 gallons overstate it.

2. 2. Under the federal tank vehicle definition, each individual tank must have a rated capacity greater than how many gallons?

   • A.250 gallons
   • B.3,000 gallons
   • C.55 gallons
   • D.119 gallons

   Answer: D. The definition covers tanks with an individual rated capacity of more than 119 gallons and an aggregate of 1,000 gallons or more. The other figures are not part of the rule.

3. 3. Your truck carries two permanently mounted water tanks, one of 600 gallons and one of 500 gallons. Do you need a tank endorsement?

   • A.Yes, together they hold 1,100 gallons
   • B.Only if the tanks are removable
   • C.No, neither single tank reaches 1,000 gallons
   • D.No, water loads are always exempt

   Answer: A. The 1,000-gallon threshold is the aggregate capacity of all tanks over 119 gallons, so 600 plus 500 gallons qualifies. The kind of liquid and whether a single tank reaches 1,000 gallons do not matter.

4. 4. You will haul liquid in a 1,200-gallon tank that is temporarily strapped to a flatbed. Which statement is correct?

   • A.Strapped tanks count as general freight instead
   • B.Only the doubles endorsement applies
   • C.The tank endorsement applies to this load
   • D.Only permanently attached tanks require the endorsement

   Answer: C. The tank vehicle definition covers tanks of 1,000 gallons or more whether permanently or temporarily attached. A strapped-down tank is not treated as general freight.

5. 5. According to the CDL manual, what is the most important item to check for on any tank vehicle?

   • A.Placard paint condition
   • B.Fifth wheel lubrication
   • C.Leaks
   • D.Tire tread depth

   Answer: C. On all tank vehicles the most important item to check for is leaks, under and around the vehicle. The other items matter, but leaks are the key tank-specific check.

6. 6. During your pre-trip inspection, you find liquid dripping from a pipe joint under the tank. What should you do?

   • A.Do not drive until the leak is fixed
   • B.Tighten the manhole cover and continue the trip
   • C.Note it on tonight's post-trip report
   • D.Drive slowly and check it at the first stop

   Answer: A. Carrying liquids or gases in a leaking tank is a crime: you can be fined, cited, and kept from driving further, and you may be liable for cleanup. The leak must be fixed first.

7. 7. When inspecting the manhole covers on top of a cargo tank, you should make sure they:

   • A.Are painted to match the tank shell
   • B.Are left slightly open for venting
   • C.Have been removed before loading
   • D.Have gaskets and close correctly

   Answer: D. Manhole covers must have gaskets and close correctly; never drive with open manhole covers. Leaving them open or removed would allow spills.

8. 8. Before loading, unloading, or moving a tank vehicle, what must you confirm about its intake, discharge, and cut-off valves?

   • A.Their handles have been removed
   • B.They are in the correct position
   • C.They have all been opened for inspection
   • D.They have been freshly greased

   Answer: B. Check that valves are in the correct position before loading, unloading, or moving the vehicle, and never drive with valves open. Greasing or removing handles is not the check.

9. 9. Which of these is special purpose equipment you should inspect on tank vehicles that have it?

   • A.Windshield washer reservoir
   • B.Grounding and bonding cables
   • C.Fifth wheel locking jaws
   • D.Mud flap brackets

   Answer: B. Special tank equipment includes vapor recovery kits, grounding and bonding cables, emergency shut-off systems, and built-in fire extinguishers. The others are ordinary truck parts.

10. 10. You are inspecting a tanker fitted with vapor recovery, emergency shut-off valves, and a built-in fire extinguisher. What should you do?

    • A.Check only the fire extinguisher
    • B.Check them only after unloading
    • C.Skip them, since only mechanics check them
    • D.Check that each system works properly

    Answer: D. If your tank has special purpose equipment, inspect it as part of your pre-trip, and know how to operate it. Mechanics alone do not cover this duty.