25 realistic Tank Vehicles practice questions for Mississippi CDL applicants. Required for: Vehicles with liquid or gaseous tanks ≥1,000 gallons. Official test: 20 questions, 16 correct to pass.
Question 1 of 25 · Backing
What should a driver do before backing a tanker?
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A.
Check the path with a helper
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B.
Look behind the vehicle
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C.
Walk around the vehicle to check clearances
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D.
All of the above
Correct answer: D.
Use a helper, walk-around, and check the path before backing.
Question 2 of 25 · Vehicle Dynamics
Why is the high center of gravity dangerous?
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A.
It increases rollover risk
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B.
It makes the vehicle more aerodynamic
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C.
It improves traction
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D.
It reduces braking force
Correct answer: A.
A high CG raises rollover risk, especially in turns or sudden maneuvers.
Question 3 of 25 · Parking
What's the safest place to park a tank vehicle overnight?
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A.
Designated truck parking areas away from buildings
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B.
On the highway shoulder
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C.
In residential areas
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D.
Anywhere with lighting
Correct answer: A.
Use designated truck parking areas away from people and buildings.
Question 4 of 25 · Tank Types
What is a "smooth bore" tank?
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A.
A tank with internal baffles
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B.
A tank without internal baffles or compartments
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C.
A heated tank
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D.
A two-compartment tank
Correct answer: B.
Smooth-bore tanks have no internal baffles, so liquid surge is unrestrained.
Question 5 of 25 · Vehicle Dynamics
What's a key safety feature in modern tankers?
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A.
Automatic emergency braking
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B.
Stability control systems
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C.
Reinforced tank shells
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D.
All of the above
Correct answer: D.
Modern tankers often combine ABS, stability control, and reinforced shells for safety.
Question 6 of 25 · Vehicle Dynamics
Why are tank vehicles often top-heavy?
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A.
The cargo is dense
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B.
The cargo's liquid weight rises with the tank shape
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C.
They have raised cargo platforms
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D.
The center of gravity is high due to liquid load
Correct answer: D.
Tank vehicles tend to have a high center of gravity, making them prone to rollover.
Question 7 of 25 · Placards
What's the role of the tanker placard?
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A.
To identify cargo for emergency responders
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B.
To indicate the vehicle is heavy
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C.
To indicate the vehicle is restricted
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D.
To warn of slow speed
Correct answer: A.
Placards identify cargo, alerting first responders to the type of hazard.
Question 8 of 25 · Inspection
What is the proper way to inspect a tank before driving?
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A.
Check valves, manhole, and tank shell for leaks and damage
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B.
Just check the tires
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C.
Only inspect the engine
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D.
Skip inspection if you're in a hurry
Correct answer: A.
Inspect valves, manhole, shell, hoses, and other tank components every pre-trip.
Question 9 of 25 · Loading
When loading tanks, what must drivers consider?
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A.
Outage requirements for the liquid
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B.
Weight distribution between compartments
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C.
Surge potential
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D.
All of the above
Correct answer: D.
Outage, weight distribution, and surge management all matter when loading tanks.
Question 10 of 25 · Vehicle Dynamics
When is liquid surge greatest?
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A.
When tanks are full
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B.
When tanks are partially full
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C.
When tanks are empty
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D.
When tanks are heated
Correct answer: B.
Surge is greatest when tanks are partially full and the liquid can move freely.
Question 11 of 25 · Adverse Conditions
What's the safe way to handle a tanker on icy roads?
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A.
Slow down and increase following distance
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B.
Use chains if required
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C.
Avoid sudden braking and steering
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D.
All of the above
Correct answer: D.
Reduced speed, chains where required, and smooth inputs reduce risk on ice.
Question 12 of 25 · HazMat Driving
Why is "no smoking" enforced near tankers?
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A.
Risk of fire and explosion from cargo vapors
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B.
Cleanliness
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C.
Tradition
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D.
OSHA rules only
Correct answer: A.
Vapors can ignite or explode; smoking is prohibited near tankers.
Question 13 of 25 · Operation
What's the recommended safe braking technique for tank trucks?
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A.
Apply brakes gradually well before stopping
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B.
Quick, hard braking
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C.
Use the engine retarder primarily
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D.
Brake at the last second
Correct answer: A.
Brake gradually and well in advance — sudden braking magnifies surge.
Question 14 of 25 · Placards
Why are tankers required to have specific markings?
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A.
To identify the cargo and any hazards
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B.
To make them more visible
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C.
For tax purposes
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D.
For insurance only
Correct answer: A.
Markings identify cargo and any hazards for emergency responders and others.
Question 15 of 25 · Tank Types
What is the purpose of internal baffles?
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A.
To reduce side-to-side surge
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B.
To reduce forward and back surge
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C.
To prevent leaks
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D.
To increase tank size
Correct answer: B.
Baffles reduce front-to-back surge but do not stop side-to-side surge.
Question 16 of 25 · Vehicle Dynamics
Why is liquid surge dangerous?
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A.
It can cause the truck to roll over
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B.
It can push the truck in the direction the wave moves
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C.
It can affect handling and braking
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D.
All of the above
Correct answer: D.
Surge can roll, push, and disrupt braking — drivers must anticipate it.
Question 17 of 25 · Vehicle Dynamics
When is it most dangerous to brake suddenly in a tanker?
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A.
When tank is partially full
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B.
When tank is fully loaded
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C.
When tank is empty
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D.
When tank is heated
Correct answer: A.
Partial loads create the most surge during sudden braking.
Question 18 of 25 · Mountain Driving
What's the proper way to handle a tanker on a steep downgrade?
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A.
Use lower gears and engine braking with intermittent service brake
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B.
Coast in neutral
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C.
Brake hard the whole way
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D.
Use the parking brake
Correct answer: A.
Lower gears and engine braking; use service brakes intermittently to avoid overheating.
Question 19 of 25 · Speed Management
When should tank drivers especially reduce speed?
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A.
On wet or slippery roads
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B.
On curves
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C.
On ramps
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D.
All of the above
Correct answer: D.
Slow down on wet roads, curves, and ramps — all increase rollover risk.
Question 20 of 25 · Tank Types
What's a key difference between compartmented and smooth-bore tanks?
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A.
Compartmented tanks reduce surge between sections
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B.
Smooth-bore tanks have less surge
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C.
They are the same in terms of surge
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D.
Compartmented tanks are always larger
Correct answer: A.
Compartmented tanks reduce overall surge by limiting movement to each section.
Question 21 of 25 · Emergencies
What action should a driver take if a tank starts to leak?
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A.
Stop immediately in a safe area and report the leak
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B.
Continue to destination
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C.
Try to close the leak
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D.
Drive faster
Correct answer: A.
Stop in a safe area, secure the area, and notify the carrier and emergency services.
Question 22 of 25 · Tank Types
What is "compartmented tanks"?
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A.
Tanks split into multiple sections
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B.
Tanks made for grain
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C.
Tanks made for hazardous materials only
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D.
Tanks with one large interior
Correct answer: A.
Compartmented tanks have multiple sections so different liquids can be carried separately.
Question 23 of 25 · Inspection
What's the importance of regular maintenance for tank vehicles?
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A.
Prevents leaks
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B.
Ensures safe operation
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C.
Identifies problems before failures
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D.
All of the above
Correct answer: D.
Routine maintenance prevents leaks, failures, and unsafe operation.
Question 24 of 25 · Speed Management
What should you do when going around curves with a tanker?
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A.
Slow down well below the posted speed
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B.
Drive at the posted speed limit
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C.
Use the engine retarder
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D.
Lock the brakes
Correct answer: A.
Take curves at speeds well below the posted limit to avoid rollovers.
Question 25 of 25 · Inspection
What's the importance of the tank shell's integrity?
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A.
It contains the cargo and prevents leaks
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B.
It supports the chassis
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C.
It absorbs shock
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D.
It connects to the brakes
Correct answer: A.
A sound tank shell prevents leaks and contains pressure from the cargo.
About the Tank Vehicles Test
The Tank Vehicles test covers inspecting tank vehicles, driving tank vehicles, surge and liquid movement, baffled and unbaffled tanks, outage, and safe driving rules unique to large liquid loads. Tank vehicles handle very differently from dry-freight vehicles because liquid surge can shove the vehicle in the direction the wave moves.
The Mississippi Department of Public Safety — Driver Services administers this knowledge test as part of its commercial driver license program. To earn the Tank Endorsement (N) on your Mississippi CDL, you need to score at least 16 out of 20 on the official version.
Topics covered on this practice test
- Vehicle Dynamics: 6 questions
- Tank Types: 4 questions
- Inspection: 3 questions
- Placards: 2 questions
- Speed Management: 2 questions
- Backing: 1 question
- Parking: 1 question
- Loading: 1 question
- Adverse Conditions: 1 question
- HazMat Driving: 1 question
- Operation: 1 question
- Mountain Driving: 1 question
- Emergencies: 1 question
How to use this practice test
- Read each question carefully. CDL questions are written precisely — small wording differences matter.
- Click "Show Answers & Explanations" only after answering every question. Don't peek mid-test.
- Read the explanation for every question, even ones you got right. The reasoning is more important than the answer.
- Repeat the test until you score 100%. The questions are deterministic per state, so you can track your improvement over multiple sessions.
- Move on to the other endorsement tests for Mississippi until you're ready for the official exam.
Tips specific to the Tank Vehicles test
Tank vehicle questions focus on liquid surge, outage, smooth-bore versus baffled tanks, high center of gravity, and the special braking and turning techniques required to keep a partially-loaded tank under control. Expect several questions about leak response and load distribution.