CDL Permit- Combination Vehicles

What type of vehicles are referred to as combination vehicles in Section 6 of the Commercial Driver's License Manual?

• Passenger vehicles

• Single vehicles

• Combination vehicles

• Motorcycles

According to Section 6.1 of the Commercial Driver's License Manual, why are combination vehicles more likely to roll over compared to single vehicles?

• They are lighter and shorter

• They have stronger commercial vehicle tires

• They are usually heavier, longer, and ride more rigidly than single vehicles

• They have more advanced braking systems

What is the effect called when a trailer turns over due to a quick lane change?

• Jackknife effect

• Rollover effect

• Crack-the-whip effect

• Bobtail effect

What is the recommended action to prevent rollovers according to Section 6.1.1?

• Drive quickly around corners

• Keep the cargo as high as possible

• Keep the cargo close to the ground and drive slowly around turns

• Load the cargo on one side to balance the turn

What should you do when approaching a turn with a combination vehicle, as suggested in Section 6.1.2?

• Speed up before going into the turn

• Change lanes or stop gently before it is too late

• Steer gently and smoothly when pulling trailers

• Follow closely behind other vehicles

What is the key advice given in Section 6.1.3 for braking with a combination vehicle?

• Brake late to maintain speed

• Brake early, especially when fully loaded

• Use panic stops frequently

• Only brake when the vehicle is empty

What is the recommended action if you get stuck on the tracks at a railroad-highway crossing?

• Continue trying to move the vehicle off the tracks.

• Get out of the vehicle and away from the tracks, and call the emergency number posted at the crossing or 911.

• Stay in the vehicle and call for help using your mobile phone.

• Wait in the vehicle for a train to pass by.

What is the phenomenon called when the wheels of a trailer lock up, leading the trailer to swing around?

• Trailer overturn

• Trailer skid

• Trailer jackknife

• Trailer spinout

According to the graph in Figure 6.1, which combination type has the highest rearward amplification factor?

• 5-axle tractor semitrailer with 45 ft.

• 3-axle tractor semitrailer with 27 ft.

• Rocky mountain double - 45 ft.

• Triple 27 ft. trailers

What is the first step in the procedure for stopping a trailer skid?

• Apply the brakes hard.

• Recognize the Skid.

• Steer into the skid.

• Release the trailer brakes.