Pennsylvania cdl Combination - Test 1
Number of questions: 20
Passing score: 80%
Acceptable number of errors: 4
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.
To DMV Handbooks2. In a vehicle equipped with an automatic tractor protection valve, the valve will pop out when:
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.