Free CDL Tank Vehicles Practice Test 2026
Learn how liquid surge, outage, bulkheads, and high centers of gravity change vehicle handling. Knowledge tests are federal: you need 80% on each one (49 CFR 383.135(a)(1)), whether you test in Texas, California, or anywhere else. QuizLane has 47 reviewed tank vehicles questions with explanations.
- Liquid surge
- Outage requirements
- Smooth braking
- Rollover prevention
Sample questions
5 tank vehicles practice questions
Each sample shows the correct answer with a plain-language explanation. The full 47-question bank is in the practice run after you pick a state.
1. How much liquid you can load depends on expansion (outage), the liquid’s weight, and:
- ASleeper size
- BRadio reception
- Legal weight limits
- DPaint color
Answer: Legal weight limits. Dense liquids may hit legal weights before the tank is full—partial fills are common.
2. Before loading, unloading, or moving a tanker, intake/discharge/cut-off valves must be:
- AWired fully open always
- BLeft randomly open
- In the correct position for the operation
- DRemoved
Answer: In the correct position for the operation. Wrong valve positions cause spills. Also check pipes, hoses, joints, manhole covers, and vents.
3. On ice, liquid surge when stopping can:
- AImprove traction
- Shove a stopped truck out into an intersection
- CEmpty the tank automatically
- DDisable the brakes
Answer: Shove a stopped truck out into an intersection. The wave hitting the end of the tank pushes the vehicle in the wave’s direction—especially dangerous on slippery surfaces.
4. The pressure relief valve on a cargo tank must be:
- ARemoved for cleaning
- BSet to the tare weight
- CSealed shut before each trip
- Free of obstruction and working correctly
Answer: Free of obstruction and working correctly. The valve prevents dangerous pressure build-up as the load warms. Blocking it risks rupturing the tank.
5. Smooth bore tanks have no baffles because they usually carry:
- Food products that require sanitary cleaning
- BDry bulk cement
- CFuel oil
- DCompressed gases
Answer: Food products that require sanitary cleaning. Sanitation rules make interior baffles impractical for food loads, so these tankers surge strongly and demand very gentle control.
Common questions
Before you start this CDL practice test
Other CDL knowledge tests
Keep going topic by topic.
- General knowledge
- Air brakes
- Combination vehicles
- Hazardous materials
- Doubles & triples
- Passenger vehicles
- School bus
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