|
Air pressure drops to a level between 20 and 45 psi.
|
|
|
You are experiencing a trailer jackknife.
|
|
|
Wheels have regained traction after a skid.
|
|
|
Air pressure is above 45 psi.
|
Pennsylvania CDL Permit Test - Combination
(From the 2020 Pennsylvania CDL driver handbook)
| Number of questions: | 20 |
| Passing score: | 16 |
Directions:
All applicants who are applying for a Class A CDL should be prepared to take the Combination test. This test covers information found in Section 6 of the Commercial Driver's Manual. Section 6 provides the information needed to safely operate tractor-trailers, doubles, triples, and straight trucks with trailers. The test is made up of 20 multiple-choice questions, and applicants will need to correctly answer a minimum of 16 questions to pass. The Combination test is not a replacement for the Double/Triple endorsement test.
Passing grade —
4 or fewer errors
advertising
1.
In a vehicle equipped with an automatic tractor protection valve, the valve will pop out when:
2.
Failure to keep the fifth wheel plate properly greased could:
|
Cause the trailer to disconnect.
|
|
|
Cause steering problems.
|
|
|
Cause braking problems.
|
|
|
Affect the lights.
|
3.
An Anti-Lock Braking System (ABS):
|
Allows wheels to lock up.
|
|
|
Prevents wheels from locking up.
|
|
|
Makes it easier to turn a large vehicle.
|
|
|
Assists with the operation of brake lights.
|
4.
Fully-loaded rigs:
|
Are less likely to roll over than empty rigs.
|
|
|
Are more likely to roll over than empty rigs.
|
|
|
Are just as likely to roll over as empty rigs.
|
|
|
Should not be driven.
|
5.
When coupling a trailer:
|
Make sure to couple matching glad hands.
|
|
|
Any glad hand can be connected to any other glad hand.
|
|
|
It is best to leave one glad hand unattached.
|
|
|
Only one set of glad hands should be connected.
|
6.
A loss of air pressure in the emergency line will cause:
|
The suspension springs to extend.
|
|
|
The tractor protection valve to open.
|
|
|
The rear trailer to detach from the combination.
|
|
|
The emergency brakes to activate.
|
7.
Trailers with low underneath clearance may be difficult to drive:
|
On interstate highways.
|
|
|
Over railroad crossings.
|
|
|
On dirt roads.
|
|
|
At the posted speed limit.
|
Ace Your DMV Written Test
Get your Cheat Sheet Now!
Get your Cheat Sheet Now!
Wait, before you go
Ace your DMV Written Test with our Guaranteed Cheat Sheet.
