Tennessee Tanker CDL Practice Test

This is a free 20-question practice test for the Tanker portion of the Tennessee Commercial Driver's License knowledge exam. Questions are pulled from a pool of 50 drawn from the AAMVA CDL Manual, which is the source document the Tennessee Department of Safety and Homeland Security Driver Services uses to write its actual exam.

How it works: Click an answer. The correct choice highlights in green, and you'll see a short explanation. Aim for 85% or better before you sit for the real test in Tennessee.

Question 1 of 20

A "smooth bore" tank has:

No internal divisions
Internal baffles
Compartments
Reinforcement rings

Correct. A smooth-bore tank has no internal divisions or baffles. Surge is dramatic; brake gently to avoid being pushed forward by the load.

Question 2 of 20

When the surge in a tanker pushes the rig forward at a stop, you may:

Brake harder
Be pushed past the intended stopping point
Skid backward
Have no effect

Correct. Forward surge can push the entire rig forward — past stop lines, into intersections, into the vehicle ahead. Plan your stops with extra distance.

Question 3 of 20

Liquid in a partially filled tank causes:

No special concern
Surge — the load slosh that affects vehicle handling
Better fuel economy
Improved braking

Correct. Surge is the side-to-side or front-to-back movement of liquid in a partially filled tank — it can throw the rig forward, pull it sideways, and significantly affect handling.

Question 4 of 20

A "baffled" tank has:

Walls with holes that slow surge but allow flow
No walls
Only one compartment
Outside reinforcement

Correct. Baffled tanks have internal bulkheads with holes — they slow surge but still allow product to flow through during loading and unloading.

Question 5 of 20

Compartmented tanks have:

Liquid-tight bulkheads dividing the tank into separate sections
No divisions
Smooth interior
Only baffles

Correct. Compartmented tanks have liquid-tight bulkheads. Each compartment is loaded separately, allowing different products in one trailer.

Question 6 of 20

Side-to-side surge is most likely to cause:

Improved fuel economy
Rollover, especially on curves and in evasive maneuvers
No effect
Better braking

Correct. Side-to-side surge can amplify side-loading forces, contributing to rollover on curves and exit ramps.

Question 7 of 20

Front-to-back surge is most likely to cause:

The vehicle to be pushed forward when braking
The vehicle to roll over
Better braking
No effect

Correct. Front-to-back surge pushes the rig forward when you brake — drivers have been pushed through stop lines by an unexpected forward surge.

Question 8 of 20

Tankers have a high center of gravity because:

The driver sits high
The load is in a tall, narrow tank
The cargo is light
The cab is wide

Correct. A tank carries its load high above the road. The center of gravity is much higher than for a flatbed of the same weight, increasing rollover risk.

Question 9 of 20

Outage refers to:

Empty space left at the top of a tank to allow liquid expansion
The brake-out system
A power failure
A driver shortage

Correct. Outage is the empty space left at the top of a tank to allow liquid to expand as it warms. Different liquids require different outage percentages.

Question 10 of 20

In the event of a fire on a tanker:

Pull off the road, away from buildings, get out, call 911, and use the ERG to identify the response
Continue to deliver
Pour water on a fuel fire
Drive faster to put out the wind

Correct. Pull to a safe area, away from buildings and people. Get out, call 911, and consult the ERG. Some tank fires (e.g., water on flammable liquid) make matters worse.

Question 11 of 20

When carrying water (a non-hazmat liquid) in a tanker, you still need:

The N endorsement, because it is a tank vehicle
No endorsement
Only the H endorsement
Just a Class B

Correct. The N endorsement is based on the vehicle being a tank, not on the cargo. Even non-hazardous water requires the N endorsement if the tank meets size criteria.

Question 12 of 20

When driving with a load that has a low specific gravity (e.g., gasoline) versus high (e.g., asphalt), you should:

Drive the same
Adjust for the differences in surge dynamics, weight distribution, and braking
Skip braking
Run hot

Correct. Different products have different densities, surge characteristics, and weight distributions. Adjust speed and braking for the load.

Question 13 of 20

Tanker pre-trip should specifically check:

Tank shell, intake/discharge/cut-off valves, manhole covers, venting devices, and pressure-relief equipment
Only the tires
Only the engine
Only the placards

Correct. In addition to standard pre-trip, inspect the tank shell, all valves, manhole covers, vents, and pressure-relief devices.

Question 14 of 20

Bonding and grounding during product transfer:

Equalizes electrical potential between the tank and receiving container, preventing static-spark ignition
Charges the battery
Cools the load
Speeds delivery

Correct. Static electricity builds up during liquid transfer. Bonding (cable between tank and receiving container) plus grounding equalizes potential to prevent ignition.

Question 15 of 20

When emergency-braking a smooth-bore tanker:

Brake hard
Anticipate forward surge that can throw your weight against the wheel and may push the rig past your intended stopping distance
Use only trailer brake
No special concern

Correct. Forward surge can dramatically push a smooth-bore tank rig further than expected. Plan stopping distance with significant additional margin.

Question 16 of 20

A tank with multiple compartments may have:

Different products in each compartment, requiring careful unloading sequence and verification
Only one product
No internal walls
No discharge

Correct. Compartmented tanks (common on fuel-delivery trucks) carry different grades or different products. Verify the destination tank before opening any discharge valve.

Question 17 of 20

Tank specification "MC-307" or "DOT-407" generally refers to:

Cargo tanks for low-pressure liquids and certain hazardous chemicals
Explosives
Bulk solids
Refrigerated gases

Correct. MC-307/DOT-407 are insulated low-pressure tanks for chemicals — common for many industrial liquids.

Question 18 of 20

A tanker with a high center of gravity is most prone to rollover during:

Straight-line driving
Tight curves, evasive maneuvers, and exit ramps
Backing
Stopping

Correct. High center of gravity makes tankers roll on tight curves, sudden lane changes, and exit ramps. Slow well in advance.

Question 19 of 20

When you discover a leak in a cargo tank carrying flammable liquid:

Continue to the destination
Stop in a safe location, secure the area, contact emergency response and the carrier — never transfer cargo on the road
Try to drive around the leak
Pour water on it

Correct. A leaking flammable cargo tank is a major incident — secure the area, evacuate per the ERG, contact emergency services. Never attempt roadside cargo transfer.

Question 20 of 20

When driving a tanker, you should:

Drive faster on curves
Drive slower than posted curve speeds, especially on exit ramps
Use only the trailer brake
Match car speeds

Correct. Posted advisory speeds assume cars. A loaded tanker may roll over at the posted speed — slow well below posted speeds for ramps and curves.

About the Tennessee Tanker exam

Most states administer 20 Tanker questions and require 80% to pass. Topics include the unique handling of liquid loads, surge effects, baffles vs. smooth-bore, outage and expansion, inspection of the cargo tank, and emergency procedures.

The Tennessee Department of Safety and Homeland Security Driver Services follows the federal CDL standards established by FMCSA. To earn the Tanker credential, you must answer at least 80% of the questions correctly. Many candidates score lower the first time because the test pulls from a large pool — refreshing this page will give you a different mix of questions, drawn from the same authoritative source.

Want more practice? Try the full Tanker question bank or browse all Tennessee CDL practice tests.