CDL COMBINATION PRACTICE TEST SOUTH CAROLINA

11. When uncoupling a trailer, after shutting off the trailer air supply to lock the trailer brakes, you should:
pull the tractor forward until the fifth-wheel comes out from under the trailer.
immediately apply your tractor parking brakes.
back up gently to ease the pressure on the fifth-wheel locking jaws.
inspect the trailer supports.
12. If an item placed on a flatbed trailer is 7 feet long, it should have __ tie-downs.
2
1
7
3
13. While driving, you should use your mirrors to:
check the condition of the tires and cargo.
know where other vehicles are around you.
check where the rear of your vehicle is while you make turns.
All of the above.
14. To be in the proper position for coupling, the fifth wheel should:
be tilted down towards the rear of the tractor.
be level with the ground.
tilted up towards the rear of the tractor.
have its jaws closed around the shank of the kingpin.
15. When you turn suddenly while pulling doubles, which trailer is most likely to turn over?
The front trailer is twice as likely to turn over as the tractor.
The rear trailer is twice as likely to turn over as the tractor.
All trailers are equally likely to turn over.
None of the above.
16. If your truck catches fire, the first thing you should do is to:
pull into a service station and call for help.
get the vehicle off the road and park near other vehicles.
pull off the road and park in an open area.
get off the vehicle, open the hood and start shooting foam to keep the engine cool.
17. The tractor protection valve:
works the trailer brakes.
controls the emergency brakes on combination vehicles.
keeps air in the tractor brake system should the trailer break away or develop a bad leak.
supplies air to the trailer air tanks.
18. Glad hands are used to:
connect the electrical lines from the truck or tractor to the trailer.
the air compressor is connected to the engine.
connect the service and emergency air lines from the truck or tractor to the trailer.
connect the brakes from the truck or tractor to the trailer.
19. At passive railroad crossings, even if there are active railroad signals that indicate the tracks are clear, you must _________  to be sure it is safe to proceed.
stop, look, and listen
listen, look and stop
go, look and put the transmission in neutral
go, stop and listen
20. A bridge formula permits less maximum axle weight for axles that:
are further apart than normal
are closer together
have poor weight balance
have a high center of gravity
GRADE ME
NOT SURE YOU WILL PASS? GET CDL PREMIUM NOW! - Learn More