CDL (Commercial Driver's License) Practice Test (Doubles & Triples #1)

Welcome future truck drivers! The following is the CDL Doubles & Triples Practice Test #1. If you're going to drive a commercial vehicle with Doubles & Triples, you'll need an Doubles & Triples Endorsement on your CDL (Commercial Driver's License). Simply click in your answer (A,B,C, or D) to each CDL practice test question. When you're done, check your score and the results. You can reset the test and retake it as many times as you want.

CDL Doubles & Triples Practice Test #1 Start Now 1. The stopping distance for a tractor trailer traveling 55 mph on dry pavement is... A Longer than a football field, about 300 feet B Two football fields, about 600 feet C Two thirds of a football field, about 200 feet D Half of a football field, about 150 feet 2. When coupling doubles, start by... A coupling the tractor to the second trailer B backing the converter dolly under the second trailer C coupling the converter tongue to the pintle hook on the first trailer D putting the second trailer against a dock 3. Trucks with double or triple trailers... A have a dangerous 'crack the whip' affect B present a rearward amplification hazard C can turn over in response to abrupt steering movements D all of the above 4. Inspect a converter dolly as if it were... A a trailer B cargo C an axle with a fifth wheel D an engine 5. To uncouple double trailers, you should park your rig... A On a slight incline B On level ground C In the company parking lot D On a soft surface 6. On trailers used as doubles and triples, you'll find shut off valves (cut off cocks) in the... A service air lines B emergency air lines C service and emergency air lines D parking brake system only 7. It is dangerous to unlock the pintle hook with the dolly still under the rear trailer because... A The dolly tow bar may fly up B The brakes might release C The kingpin might break off D The fifth wheel might not be aligned 8. A drive-wheel skid when pulling doubles could result in a jackknife when... A The tractor brakes lock up B The trailer pushes the towed vehicle sideways C The trailer slides off the right side of the road D The tractor spins around 9. To check for air flow to the last trailer... A Pull forward and step on brake pedal B Open emergency shut off valve and listen for escaping air C Step on brake pedal and watch for brake lights D Test emergency brake lines on level surface 10. You should test your tractor protection valve to avoid... A The emergency brakes coming on due to loss of air B The loss of air from the air hose C The loss of air from your trailer brakes D All of the above 11. To test the trailer service brakes you should... A Lightly test brakes at 5 mph B Apply hand control and check to see if you feel the trailer brakes come on C Depress the brake pedal D Release air to the brakes 12. When pulling triple trailers, which unit is more likely to roll over? A The front trailer B The middle trailer C The last trailer D The tractor 13. When pulling triple trailers, always put the heaviest trailer... A In the front B In the rear C In the middle D It doesn't make a difference 14. When inspecting doubles, the shut off valves at the rear of the trailer should be... A Open at the rear of front trailer, open at the rear of the last trailer B Open at the rear of front trailer, closed at the rear of the last trailer C Closed at the rear of front trailer, closed at the rear of the last trailer D None of the Above 15. When steering to avoid a crash while pulling doubles, remember to... A Keep both hands on the steering wheel B Stay off the brake while turning C Be prepared to counter-steer D All of the above 16. When coupling the rear trailer, the correct trailer height is... A Six inches of space between the upper and lower fifth wheel B Slightly lower than the fifth wheel C When the locking jaws are closed around the kingpin D The kingpin touches the fifth wheel 17. When connecting the converter dolly to the rear trailer, you should remember to... A Make sure trailer brakes are locked B Make sure trailer height is correct C Raise the landing gear slightly off the ground D All of the above 18. Should you unhook the pintle hook with the converter dolly still under a trailer? A Yes, this is standard procedure B Yes, this keeps the trailer from falling C No, this could damage the pintle hook D No, this could result in your injury 19. When coupling twin trailers, you should release the dolly brakes by... A Dropping the trailer onto the fifth wheel B Opening the air tank petcock C Letting the air out of the brake line D Pushing the air release valve on the dash 20. To uncouple the converter dolly you should: A Disconnect safety chains, lower the landing gear and chock the wheels B Chock the wheels, lower the landing gear and disconnect safety chains C Lower the landing gear, disconnect safety chains, and chock the wheels D Chock the wheels, disconnect safety chains, and lower the landing gear Score = Correct answers: Get My CDL! The New Trucker Career Center CDL Practice Tests Access Page Trucker Country Home Page Choose from these additional practice tests... CDL General Knowledge Practice Test #1 CDL General Knowledge Practice Test #2 CDL Hazardous Materials Practice Test #1 CDL Hazardous Materials Practice Test #2 CDL Air Brakes Practice Test #1 CDL Air Brakes Practice Test #2 CDL Doubles and Triples Practice Test #2 CDL Combination Vehicles Practice Test #1 CDL Combination Vehicles Practice Test #2 CDL Tank Vehicles Practice Test #1 CDL Tank Vehicles Practice Test #2 Jim Purcell, President of Trucker Country, has put together the ultimate series of trucking guides for anyone interested in a career as a professional trucker. Whether you're just curious about trucking or you're ready to become a successful truck driver, you'll find all the real-world information you need in this amazing series of guides. Learn, step-by-step: the truth about the world of trucking, how to become a trucker, and even how to succeed at the trucking job and life.

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