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A tanker has stopped on ice just before an intersection. The wheels are no longer rolling. What danger can remain?
What the Tank Vehicles test covers
Questions come from the tank vehicles section of your state's CDL manual. Expect questions on inspecting a tank, how tank construction affects handling, how much to load, and driving smoothly to control surge.
Surge, baffles, and bulkheads
When a wave of liquid hits the end of the tank, it pushes the truck in the direction the wave is moving. On a slippery road, that can shove a stopped truck into an intersection. Brake well ahead of time, keep steady pressure, don't let off too soon, and leave extra following distance.
Bulkheads divide a tank into compartments. Watch the weight distribution so there isn't too much weight at the front or rear. Baffles help control front-to-back surge, but side-to-side surge can still happen and can help cause a rollover. A smooth-bore tank has no baffles, so front-to-back surge is very strong. Be extra careful starting and stopping.
Tanks have a high center of gravity, which makes them top-heavy and easier to roll over. A posted curve speed may be too fast for a tank vehicle.
Inspection and loading
For every tank vehicle, leaks are the most important thing to check. Never carry a load in a leaking tank. Check the intake, discharge, and cut-off valves, make sure manhole covers have good gaskets, and keep vents clear. Don't drive with valves or manhole covers open.
Don't fill a tank all the way, because liquids expand. The space you leave is called outage. Dense liquids may reach the legal weight limit before the tank is full.
Common questions
How many questions are on the CDL Tanker test?
It varies by state, but it's usually around 20 questions. You need 80% to pass.
Does an empty tank stop faster than a full one?
Not necessarily. An empty tank vehicle may take longer to stop than a full one, because there's less weight pressing the tires to the road. On wet roads, give yourself even more room.
What's the X endorsement?
X is a combined HazMat and Tank endorsement, for hauling hazardous materials in a tank. You pass both the HazMat and Tank Vehicles tests to get it.
Questions and explanations
Prefer to read? Review the same 10 practice questions here. These are original study questions, not official exam questions. Our practice questions include explanations to help you return to the relevant official manual material.
A tanker has stopped on ice just before an intersection. The wheels are no longer rolling. What danger can remain?
Liquid surge can push the stopped truck into the intersection.
On ice, a moving wave of liquid can push a tanker that has already stopped into the intersection.
When should you check a tank vehicle to make sure it's safe for its cargo and safe to drive?
Before loading, unloading, or driving.
The check comes before each of these jobs, so you know the cargo and the vehicle are safe.
Traffic ahead is slowing normally. Which plan best helps a tanker driver control surge and keep room to stop?
Follow farther back, brake well ahead of time, and keep steady brake pressure.
More following distance and earlier braking make room. Steady brake pressure helps control surge during the stop.
Your check finds signs that the tank is leaking. What is the right call?
Do not carry a load in the leaking tank.
Leak checks are the top priority. A leaking tank must not carry a load.
You're driving an empty tank vehicle on a wet road. How should you plan your stopping room?
Allow extra room. Wet roads add stopping distance, and an empty tank may take longer to stop than a full one.
Both the wet road and the chance of a longer empty-tank stop mean you should allow more room.
How should you handle special-purpose tank equipment during a readiness check?
Check any special-purpose items the tank has to make sure they work.
Items like recovery kits, cables, shut-offs, or built-in extinguishers get checked when the vehicle has them.
A rig pulling a tank trailer starts to skid at the tractor drive wheels. What risk should the driver recognize?
The skid may lead to a jackknife.
With a tank trailer, a skid that starts at the drive wheels or trailer wheels may turn into a jackknife.
Bulkheads divide a tank into compartments. What should guide how you load it?
The real weight distribution from front to rear.
With compartments, you still watch distribution so too much weight doesn't end up at either end.
Which statement says what baffles do and don't do?
They help control front-to-back surge, but side-to-side surge can remain.
Baffles slow front-to-back movement. Side surge can remain and can help cause a rollover.
How should you handle a smooth-bore tank?
Use extra-careful, smooth starts and stops.
There are no baffles to slow the flow. Strong front-to-back surge calls for careful starts and stops.
Study sources and limitations
Editorial attribution: Evergreen Comply, LLC Editorial Staff. Our practice questions include explanations to help you return to the relevant official manual material.
Use your current state manual and a qualified instructor for licensing requirements and hands-on procedures. This practice set does not replace required training or certify readiness to drive.
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Source links checked September 25, 2026.
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