Making a sudden lane change can be dangerous when driving a combination vehicle. Avoid the need to make a sudden lane change by looking down the road for upcoming obstacles that will require you to change lanes.

Watching the road ahead while driving.

Using your horn to encourage other drivers to move out of your lane.

Only driving slower than the posted speed limit.

Watching the road ahead while driving.

Pulling off the road and waiting when there is high traffic.

Cargo weight should be evenly distributed within a trailer to reduce the risk of a rollover. Do not place too much weight on one side of a trailer.

Loaded with most weight on the driver’s side of the trailer.

Placed near the rear of the trailer.

Tractors without semi-trailers are referred to as bobtail tractors. Operating a bobtail tractor requires drivers to exercise caution.

A tractor attached to two trailers

The trailer hand valve, also called the trolley valve or Johnson bar, is used to work the trailer brakes. It should be used only to test the brakes. Using it while a vehicle is in motion could cause a skid.

A hand valve that works the trailer brakes

A valve that indicates the fuel level

A valve that limits the amount of cargo

Tractor protection controls in older vehicles may be operated by levers instead of knobs. If an air supply control is set in its "emergency" position, the air supply will be stopped and the trailer emergency brakes will be applied.

The trailer emergency brakes will be applied.

The vehicle will increase speed.

The trailer emergency brakes will be applied.

The air supply to the trailer will increase.

If a trailer begins to jackknife, you should release the brakes and allow the trailer wheels to regain traction with the road. Do not apply the trailer hand brake to attempt to straighten out the rig because the application of brakes is what caused the wheels to lock in the first place.

Should not apply the trailer hand brake.

Should firmly apply the brakes.

Can straighten the trailer with the parking brake.

Positioning the weight of a load on one side of a trailer may cause the trailer to lean to that side, increasing the risk of a rollover during turns and lane changes.

May add extra support during turns.

May be easier to steer during turns.

Combination Vehicles Practice Test | Utah 2025 #1

Train for FREE online with our Utah CDL combination vehicle test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a UT combination license in 2025, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that DMV requirements for issuing a combination license may vary from state to state.

Number of Question 30

Passing Score 25

Number of Tests 20

Combination Vehicles Practice Test | Utah 2025 #1

1 . Avoid needing to make sudden lane changes by:

2 . To prevent a rollover, cargo should be:

3 . What is a bobtail tractor?

4 . What is the Johnson bar?

5 . What is another name for the service line?

6 . If an air supply control is in its "emergency" position:

7 . If a trailer begins to jackknife, the driver:

8 . If a load is placed on one side of a trailer, the trailer:

See the exact questions that will be on the 2025 DMV exam.

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