Combination Vehicles Flashcards
Which of the following is NOT part of testing the tractor protection valve?
Pulling forward slowly, then applying the trailer brakes.
As part of the final air brake check, you should:
Check air compressor governor cut-in and cut-out pressure and test air leakage rate.
Most hydraulic brake failures occur for one of two reasons, one of which is:
loss of hydraulic pressure.
You are driving a heavy vehicle with a manual transmission, and you have to stop on the shoulder while driving on an uphill grade. When putting your vehicle back in motion up the grade, you should:
use the parking brake to hold the vehicle until the clutch engages.
Banked curves:
have a safe “design speed”.
If your vehicle is equipped with air brakes, loss of air pressure in the emergency line causes:
the trailer emergency brakes to come on.
A bridge formula permits less maximum axle weight for axles that:
are closer together
After coupling the trailer, begin raising the landing gear by using:
the low gear range.
Which of the following statements about off-tracking is true?
If there is more than one trailer, the rear wheels of the last trailer will off-track the most.
What is a tractor jackknife?
When a drive-wheel skid lets the trailer push the towing vehicle sideways.
When backing a truck you should:
get out and walk around the vehicle before you begin to back.
When coupling a tractor to a semi-trailer, after checking if the fifth-wheel is in proper position for coupling you should:
make sure the area around the vehicle is clear and the trailer wheels are chocked.
Before driving a vehicle with a dual air brake system, you should allow time for the air compressor to build up a minimum of ____ pressure in both the primary and secondary systems.
100 psi
When transporting cargo, the cargo should be checked:
before the trip and after the first 50 miles.
correct air valves for testing the trailer springs/parking brakes
service brake: off
parking brake: off
trailer air supply: out
trolley released
