Montana Tanker CDL Practice Test

This is a free 20-question practice test for the Tanker portion of the Montana 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 Montana Motor Vehicle Division 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 Montana.

Question 1 of 20

A "tank vehicle" requiring an N endorsement is generally defined as:

Any commercial vehicle
A vehicle used to transport liquid or gaseous materials in a tank with rated capacity of 1,000 gallons or more, individual tanks of 119+ gallons
Only fuel trucks
Only vehicles over 80,000 lbs

Correct. The N endorsement is required for any commercial vehicle hauling liquid or gas in a permanently mounted tank or portable tank with rated capacity of 1,000+ gallons (and individual tanks of 119+ gallons).

Question 2 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 3 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 4 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 5 of 20

A pressure-relief device that vents during transit:

Is a normal occurrence
Is a serious malfunction or over-fill — stop and investigate
Means the tank is empty
Means the load is cold

Correct. Continuous venting indicates over-pressure (often from over-fill or sun heating an over-filled tank). Stop and investigate; do not continue with a venting tank.

Question 6 of 20

Tankers should be driven with:

Less following distance
More following distance and gentler control inputs than a dry van
The same as a car
Higher speeds

Correct. Tankers stop slower and roll easier. Increase following distance and use gentler steering and braking inputs.

Question 7 of 20

When you drive a tanker on slippery roads, you should:

Drive faster
Reduce speed substantially and increase following distance
Use only the trailer brake
Maintain normal speed

Correct. Reduce speed by at least one-third on wet roads, by half on snow. Liquid loads make recovery from a skid much harder.

Question 8 of 20

Empty tankers handle:

The same as loaded tankers
Differently — lighter axle weight reduces braking traction; tankers are also more affected by crosswinds when empty
Always better
Always worse

Correct. Empty tankers have less brake traction (less weight on tires) and are more affected by crosswinds. Never assume empty equals safer.

Question 9 of 20

Tank vehicles should not be driven:

On long downgrades without a lower gear and intermittent firm braking
On any highway
Anywhere
At night

Correct. On long downgrades, select a low gear before starting down and use firm intermittent brake applications to prevent fade.

Question 10 of 20

When unloading product from a cargo tank, you should:

Verify the receiving container can hold the load, bond and ground, control the flow rate, and remain within 25 feet for flammables
Walk away
Maximize flow rate
Smoke nearby

Correct. Pre-check receiving container, bond and ground, control flow rate to prevent splash and spill, and remain attentive for flammable liquids.

Question 11 of 20

When loading a cargo tank with flammable liquid, the driver must:

Stay alert, within 25 feet, with a clear view of the tank, and ready to handle emergencies
Leave for lunch
Smoke
Run the engine at high RPM

Correct. Federal rule: driver remains within 25 feet, alert, with a clear view, ready to act in case of overflow or emergency.

Question 12 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.

Question 13 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 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

When you stop a placarded tanker carrying flammable liquid at a railroad crossing, you must stop:

On the rails
Between 15 and 50 feet from the nearest rail, then proceed only when safe
Anywhere
Only if a train is in sight

Correct. Placarded hazmat (which most fuel tankers are) must stop 15 to 50 feet from the nearest rail. Look, listen, and cross only when clear.

Question 17 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 18 of 20

When braking a partially filled smooth-bore tank, you should:

Brake hard at the last minute
Brake gently and start braking earlier than usual to compensate for surge
Use only the trailer hand valve
Pump the brakes

Correct. In smooth-bore tanks, surge is severe. Brake gently and earlier than you would in a dry-van trailer to avoid being pushed forward.

Question 19 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 20 of 20

A loaded tanker on a curve is most likely to:

Roll over because surge plus high CG amplifies side forces
Skid in a straight line
Brake faster
Steer easier

Correct. Side surge plus high CG creates a tipping moment well above what a flat-bed of equal weight produces. Speed reduction in advance is the only safe answer.

About the Montana 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 Montana Motor Vehicle Division 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 Montana CDL practice tests.