Combination
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 California Commercial Driver Handbook. 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 17 questions to pass. The Combination test is not a replacement for the Double/Triple endorsement test.
Passing grade:
A loss of air pressure in the emergency line will cause:
Explanation
The emergency air line controls the emergency brakes on a combination vehicle. A loss of air pressure in the emergency line will cause the emergency trailer brakes to activate.
When connecting a converter dolly to a second trailer, the trailer height should be ____ the center of the fifth wheel.
Explanation
When connecting a converter dolly to a second or third trailer, the trailer height should correct. It should be slightly lower than the center of the fifth wheel.
In a sudden turn, the ____ trailer is the most likely to turn over.
Explanation
When making a turn, be sure to steer gently and smoothly. Making a quick turn while pulling trailers is dangerous and can increase the risk of the last trailer rolling over.
After completing a pre-trip inspection, you should ensure that the:
Explanation
Before a trip, you should ensure that air reaches all air brakes on all trailers by opening up the rear emergency line and service line shut-off valves and listening for escaping air. Close both shut-off valves before beginning to drive.
All trailers made after ____ must be equipped with Anti-Lock Braking Systems (ABS).
Explanation
All trailers and converter dollies manufactured on or after March 1, 1998 must have Anti-Lock Braking Systems (ABS).
An air supply control lever should be in its "normal" position when you are:
Explanation
Tractor protection controls in older vehicles may be operated by levers instead of knobs. If an air supply control is set in its "normal" position, it is properly set for you to pull a trailer.
How much space should be between the upper and lower fifth wheel?
Explanation
