View instructions
Drivers who want to drive combination vehicles must pass the combination vehicles test. The Oregon CDL combination test consists of 20 questions, and you'll need at least 16 correct answers to pass (80%). The test covers the combination vehicles section of the Oregon CDL Manual. Take this practice test now to prepare for the actual OR CDL combination test!
1.
With brake drums, if brakes become too hot:
|
your ABS will malfunction.
|
|
|
the brakes may stop working.
|
|
|
the air compressor will kick on to cool the brakes.
|
|
|
the brakes will supply too much power to the drive wheels.
|
2.
Over-length loads:
|
require special driving care.
|
|
|
require special transit permits.
|
|
|
may require special equipment such as "wide load" or flags.
|
|
|
All of the above.
|
3.
When you back under a trailer:
|
back the tractor slowly.
|
|
|
make sure the trailer brakes are locked.
|
|
|
use lowest reverse gear.
|
|
|
All of the above.
|
4.
The tractor protection valve:
|
supplies air to the trailer air tanks.
|
|
|
works the trailer brakes.
|
|
|
keeps air in the tractor brake system should the trailer break away or develop a bad leak.
|
|
|
controls the emergency brakes on combination vehicles.
|
5.
Loose cargo:
|
could hurt or kill you during a quick stop.
|
|
|
can be a danger to others and yourself.
|
|
|
could fall off your vehicle and cause traffic problems.
|
|
|
All of the above.
|
6.
You have two tie-downs on a 15 foot load. How many more tie-downs do you need to secure cargo and keep it from shifting or falling?
|
Three
|
|
|
One
|
|
|
None
|
|
|
Two
|
7.
If loose or missing, _______ may cause movement between the frame and fifth wheel assembly.
|
mounting bolts
|
|
|
electric connectors
|
|
|
locking pins
|
|
|
safety chains
|
8.
When checking the air and electric lines to the trailer, be sure that the air lines are properly connected to the gland hands, and are:
|
properly greased.
|
|
|
secured with enough slack for turns.
|
|
|
secured with enough air leaks for turns.
|
|
|
None of the above.
|
9.
If your truck has automatic transmission, you should downshift:
|
whenever road conditions allow.
|
|
|
when going down grades.
|
|
|
after entering a curve.
|
|
|
when you need to accelerate.
|
10.
The emergency air line does NOT:
|
pump air into the relay valves, allowing the trailer brakes to be applied more quickly.
|
|
|
control the emergency brakes on combination vehicles.
|
|
|
supply air to the trailer air tanks.
|
|
|
cause the tractor protection valve to close when the emergency line loses pressure.
|
Page 1 of 2
Next page
Grade this page