FREE Minnesota Combination Practice Test (2023)

1. When backing a trailer, you should:

not back up in a straight line.
pull-up frequently to reposition the vehicle.
avoid braking.
turn the steering wheel toward the direction you want to go.

2. When you are uncoupling a loaded trailer, lower the landing gear until:

makes contact with the ground, and leave the trailer off the fifth wheel.
the pressure in the system is above 55 psi.
the tractor frame is under the trailer.
it makes firm contact with the ground.

3. Dual tires:

should come in contact with each other whenever possible.
should not come in contact with each other.
are dangerous.
should always come in contact with each other.

4. You supply air to the trailer brake system by:

pulling out the trailer air supply valve.
pushing in the trailer air supply knob.
connecting the tractor service air line to the trailer service glad hand.
plugging the electrical cord into the trailer.

5. Which of the following is NOT part of testing the tractor protection valve?

Shutting off the engine.
Stepping on and off the brake pedal several times to reduce the air pressure in the tanks.
Pulling forward slowly, then applying the trailer brakes.
Charging the trailer air brake system.

6. When you make a quick lane change, the crack-the-whip effect can:

improve your traction.
the trailer to swing wide to the left.
make it harder to turn without skidding.
turn the trailer over.

7. Tests have shown that trucks with a high center of gravity:

can roll over if the driver exceeds the posted speed limit for a curve.
can roll over if the driver slows down before entering a curve.
can roll over at the posted speed limit for a curve.
are less likely to roll over when entering a curve.

8. Inspecting the fifth-wheel does NOT include:

making sure that the fifth wheel is in the proper position for coupling.
checking for missing or damaged parts.
checking that there are no cracks in the frame.
backing until the fifth-wheel just touches the trailer.

9. When transporting cargo, the cargo should be checked:

before the trip and after the first 150 miles.
before the trip and after the first 50 miles.
only before the trip.
only after the trip.

10. "Bobtail" tractors are:

tractors with two trailers.
heavily loaded trailers.
tractors without semitrailers.
tractors with a tank.

CDL COMBINATION PRACTICE TEST MINNESOTA