Texas CDL — General Knowledge: Traffic Laws Practice Test

Question 1

Under federal rules, how may a commercial driver use a mobile phone while driving?

Accepted Answer

Only hands-free, without holding or reaching for the phone — FMCSA bans holding or reaching for a hand-held phone while driving a commercial vehicle. Only hands-free use, with the phone within reach and operated by a single touch, is allowed.

Answer

Freely, holding the phone in one hand

Answer

Only while stopped at a red light, holding it up

Answer

There are no federal limits on phone use

Question 2

At night, cargo that sticks out more than four feet past the back of your vehicle must be marked with:

Accepted Answer

A burning red lamp that can be seen from 500 feet — During daylight a red flag of at least twelve inches square marks the end of the overhang. Once it is dark, that marker has to be a burning red lamp visible from 500 feet away.

Answer

A white flag measuring at least twelve inches square

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An amber strobe mounted on the cab roof

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Two orange cones tied to the rear bumper

Question 3

When your truck is following another truck on a Texas highway, the law expects you to:

Accepted Answer

Hang back far enough that a passing vehicle could pull in between you — One truck trailing another has to hang back far enough that a passing vehicle can slip into the gap safely. The rule does not stop you from overtaking and passing the truck ahead.

Answer

Stay within a vehicle length so nobody can cut in

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Match the speed of the truck ahead exactly

Answer

Keep at least half a mile of space at all times

Question 4

A posted speed limit tells a commercial driver:

Accepted Answer

The maximum legal speed in ideal conditions, which may be too fast when conditions are poor — The posted limit is the maximum legal speed under ideal conditions. In rain, fog, heavy traffic, or on a downgrade, a safe speed for a large vehicle is often well below the limit.

Answer

The exact speed you must always travel

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A minimum speed set only for trucks

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A speed you may exceed when you are running late

Question 5

Hauling dirt, sand, gravel, or wood chips over a Texas public highway is allowed only when:

Accepted Answer

The bed is closed on every side or the load is covered and tied down — Loose material that could blow or spill has to be shut in by a bed closed on all four sides, or else covered by a tarp or canvas tied down front and rear so nothing escapes.

Answer

The truck avoids the interstate system

Answer

The driver is carrying an oversize permit

Answer

The load is weighed at every county line

Question 6

Under the Texas operating rules for commercial vehicles, coasting down a grade is:

Accepted Answer

Against the law, so choose your lower gear before the descent begins — A commercial vehicle may not coast down a hill, and holding the clutch in while the transmission stays in gear does not make it legal. Choose the lower gear you need before the descent starts.

Answer

Allowed as long as the clutch stays engaged

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Permitted whenever the load is under 10,000 pounds

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Legal only on interstate highways

Question 7

Counting the freight it carries, how tall may a vehicle legally be in Texas?

Accepted Answer

No more than 14 feet from the ground to the top of the load — State law caps total height at 14 feet measured from the pavement to the highest point of the load, and the driver is the one responsible for making sure the load clears every bridge and overpass on the route.

Answer

No more than 12 feet

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No more than 16 feet

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There is no state limit on height

Question 8

Every commercial motor vehicle running on a Texas public highway must carry registration papers showing:

Accepted Answer

What the vehicle weighs empty and the weight it is registered to haul — The receipt for the license plates has to ride with the vehicle, and it must state both the empty weight of the unit and the weight it is registered to haul.

Answer

The number on the driver's medical examiner certificate

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A copy of the shipper's invoice for the current load

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The route the carrier has filed with the state

Question 9

Wearing your seat belt while driving a commercial vehicle is:

Accepted Answer

Required, and it helps you keep control and survive a crash — Seat belts are required and save lives. A belted driver is far more likely to keep control of the vehicle and survive a crash.

Answer

Optional for experienced drivers

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Needed only on the highway

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Unnecessary in a large, heavy vehicle

Question 10

Without an oversize or overweight permit, the most a vehicle or combination plus its cargo may weigh in Texas is:

Accepted Answer

80,000 pounds — Eighty thousand pounds is the ceiling for any vehicle or combination including its load. Going above it takes a permit issued through the state transportation department.

Answer

60,000 pounds

Answer

100,000 pounds

Answer

26,001 pounds

Texas CDL — General Knowledge: Traffic Laws practice test

Study questions with answers

1. Under federal rules, how may a commercial driver use a mobile phone while driving?

2. At night, cargo that sticks out more than four feet past the back of your vehicle must be marked with:

3. When your truck is following another truck on a Texas highway, the law expects you to:

4. A posted speed limit tells a commercial driver:

5. Hauling dirt, sand, gravel, or wood chips over a Texas public highway is allowed only when:

6. Under the Texas operating rules for commercial vehicles, coasting down a grade is:

7. Counting the freight it carries, how tall may a vehicle legally be in Texas?

8. Every commercial motor vehicle running on a Texas public highway must carry registration papers showing:

9. Wearing your seat belt while driving a commercial vehicle is:

10. Without an oversize or overweight permit, the most a vehicle or combination plus its cargo may weigh in Texas is:

More CDL — General Knowledge topics

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