1. 0000004689 00000 n
Park on level ground, put chock on the tires, and charge the air tank. True or False? Which of the following will occur? Only a certified diesel mechanic can check this. d. protein. The dolly tow bar may fly away, possibly causing panic, and making it very difficult What does the Commercial Driver Handbook say about how much space you should keep ahead of your truck? Doubles and triples are more likely to overturn than other combination vehicles because of the whip cracking effect. A. always keep your vehicle to the right side of your lane If your tanks have automatic drains, they will keep most moisture out, but you should still open the drains to make sure. You should keep at least ____ seconds of space ahead of you. How many different ways of coupling and uncoupling trailer combinations are there? Our normal business hours are Monday-Friday 8 a.m. to 5 p.m. (Pacific Time). 10 There is no requirement or exact standard for color coding. A green traffic light allows the driver to go. "Glad hands" are coupling devices used to connect the service and emergency air lines from the truck or tractor to the trailer. 0000010705 00000 n
Hit the article to see the way to back up your trailer like a pro! 0000008166 00000 n
Contributor: Luke Nold (Experienced truck driver for 5+ years and published writer for Fleet Magazine). 0000001107 00000 n
If spare tire is on converter gear (dolly), make sure it is secured. door. A. require shorter stopping distances than full ones Simply click in your answer to each CDL practice test question. Any trailer with a reduced ground clearance 0000006195 00000 n
The converter dolly air tank drain valve on coupled double and triple trailers should be: Closed. What types of trailers can get stuck on raised crossings? 21 0 obj
<<
/Linearized 1
/O 23
/H [ 1162 213 ]
/L 29759
/E 11109
/N 7
/T 29221
>>
endobj
xref
21 38
0000000016 00000 n
The dolly will have a yellow lamp on the drivers (left) side. Which of these statements about managing space to the sides is true? A. brake and downshift in a curve c. iron TestPermit.com is not affiliated, endorsed, or sponsored by state agencies or any motor vehicle and any other departments in the United States, Canada, UK. You are driving a tractor with multiple trailers. This would be very dangerous. Any vehicle required by federal regulations to be placarded while transporting hazardous materials. weather passes. Safety chains should be secured to trailer(s). Converter dollies are connected to front trailers with a? Correct answer percentage. Air escape from the open valve You are driving with double trailers and must use your brakes to avoid a crash. You should keep at least ___ seconds of space ahead of you. Only trailers designed to be pulled with another trailer behind it will have a shut off valve. securely fastened. A The application only takes one minute. How can you test that air flows to all trailers? When coupling twin trailers, you should _______ the pintle hook and secure the dolly support in the _______ position. A. opening the air tank petcock The pressure in the service line is controlled by the brake pedal and the trailer hand brake. How much space should be between the upper and lower fifth wheel? The weight of the individual trailers will have no noticeable effect on the handling of the vehicle, The weight of all trailers should be nearly the same, within 2% of each other. 0000002446 00000 n
Pull gently against them in a low gear to make sure the brakes work. Eventually, the air will leak away, and then there will be no brakes. How should you test the coupling? How do you check to make sure the trailer height is correct before coupling? A low air buzzer will go off indicating something is wrong and either the front or the second trailer will be connected, The dolly will have a yellow lamp on the left side, The dolly will have a yellow lamp on the right side, The dolly will have a red lamp on the left side, The dolly will have a red lamp on the right side. These mirrors: make things seem smaller & further away then they really are. View More Details. You may be timed. Shut-off valves (also called cut-out cocks) are used in the service and supply air lines at the back of trailers used to tow other trailers. Which of the following must be connected when coupling tractor to trailer or trailer to trailer? The rear trailers shut-off valves should be closed and the front open. rear trailer. What should you check for when inspecting the converter dolly and the pintle hook? 0000010783 00000 n
Tractor-trailers are considered combination vehicles. 0000005733 00000 n
Optional: Leave your email address if you would like a reply: When inspecting doubles or triples, in what position should the air shut-off valves be in? What is a converter dolly? To check air flows to all trailers, you should let air pressure reach normal then? Becoming A Truck Driver is a dream we've all pondered at some point in our lives. fifth wheel, so trailer is raised slightly when dolly is pushed under it. On the middle trailer of a set of triples? Never unlock the pintle hook with the dolly still under the rear trailer. When checking the fifth wheel, you should make sure that it has enough? When does the "driver's manual" advise disconnecting the steering axle brakes to help keep the rig straight? What should you check for when inspecting a converter dolly? Should the pintle hook be latched or unlatched when backing a dolly under the second trailer? In normal operation, trailer service brakes should be operated by? A. the total stopping distance of a truck is the distance it takes to stop once the brakes are put on at any speed You should keep at least _____ seconds of space ahead of you. The rear trailer of a double You should be sure the converter dolly air tank drain valves are ____ and the pintle hook is ____. When connecting the glad hands, press the two seals together with the couplers at a 90-degree angle to each other. Like a trailer, a dolly equipped with ABS will have a yellow indicator light on the left side. 12, 3. when testing the coupling of a double trailer the landing gears of the rear trailer should be, you must drive through deep or flowing water . Locking jaws open 0000001956 00000 n
You must steer gently when pulling trailers. Each trailer and converter dolly has one or more air tanks. When entering a roundabout, a driver must yield the right-of-way to drivers already in the roundabout and obey all traffic signs. What value of channel width must the design use? unsafe slow down even further, or better yet, find a safe haven and park until the If you do, the brakes may not work correctly. A. use light, steady pressure on the brake pedal 1) the first one is to pump down the air pressure in the system between 20 and 45psi (pounds per square inch) the trailer air supply will pop out, shutting air off to the trailer. These mirrors: Make things seem smaller and further away than they really are. cQ
220rd8bihuM#Om>G*Lz)g^\l9'A9/omf|b49U[@%jGT-QR6i. 2) the second test is to go out to the trailer to ensure that the parking brakes have indeed applied. However there are some states that allow doubles that are each 48 feet in length. The converter dolly air tank drain valve on coupled double and triple trailers should be: When inspecting coupled doubles and triples, make sure the pintle hooks are: How can you be sure you supplied air to a second trailer? A major leak in the emergency line will cause the tractor protection valve to close and the trailer emergency brakes to come on. When you do this, you should hear: you are driving with double trailer and must use your brakes to avoid a crash. All of the above, 6. A. air escape from the open valve Stay up to date on truck driving industry news. 11 When only pulling one trailer, be sure the shut-off valves are all in the fully closed position. Which of the following will probably happen if you are driving a double rig and a set of trailer wheels goes into a skid? allow "much more space than is needed for ideal driving conditions". Closed, free, 8. We have a new version of this program. C. back up slightly and make a visual check of the coupling, You are driving with double trailers and must use your brakes to avoid a crash. Describe what the trailer air supply control does. A. use the engine brake or speed retarder The Verge logo. A dolly has lights, air tanks, air relays, air lines, air brakes, ABS, electrical connections, etc. C kingpin, That there is grease between upper and lower fifth wheel. Open the emergency line shut-off valve at the rear of the last trailer. Which of these is most likely to occur? Stop the vehicle by gearing down and sparingly A major leak in the emergency line will cause the tractor protection valve to close and the trailer emergency brakes to come on. By clicking on "Sign Up", you agree to our Terms of Use and Privacy Policy. Their drawbars differentiate them. 0000001354 00000 n
D You will speak with recruiters today. 27. Connect Converter Dolly to Front Trailer Back first semitrailer into position in front of dolly tongue. That there is no space between upper and lower sixth wheel. If the fifth wheel on a coupling is too far forward, the tractor frame may hit? Time used (Requires timer add on). What happens if you cross the Emergency Air Line and the Service Air Line? To do this without wheel chocks you should: Empty trucks: When parking your double or triple combination, you should look for a parking space the rig will continue moving in a straight line no matter how much the steering wheel is turned. There are more things that can go wrong, and doubles/triples are less stable than other commercial vehicles. Pintle hook latched. All ABS equipped units Converter dolly air tank drain valve: CLOSED Air lines supported and glad hands properly connected. Why should you pull a dolly out from under a trailer before you disconnect it from the trailer in front? Trailer Air Tanks And Shutoff Valves - Page 50. C. posted speed limits on curves are safe for all trucks, Empty trucks: Air pressure is sent from the air tanks to the brakes by relay valves. CDL License Requirements State By State. Pull gently against the pin of the second trailer. Air escape from the open valve B The service brakes slowly move to the fully applied position C The emergency line valve open and release air D None of the above 4. 0000001582 00000 n
Should the converter dolly air-tank drain valve be open or closed on a double trailer combination? you are driving on a slippery road during the day. When driving doubles or triples how should they be driven to avoid rollover or jackknifing: Also, this page requires javascript. Air flows steadily and isentropically through a passage. You are driving with double trailers and must use your brakes to avoid a crash. A. release the spring brakes and check for movement How much space should be between the upper and lower fifth wheels? If there is a trailer Unlock the pintle hook only if the trailer it is under is loaded, otherwise the dolly tow bar may fly up, possibly causing injury and making it very difficult to re-couple. Before coupling a trailer, you should make sure it is at the right height using? The service air line is only used to control the service brakes (when you press on the brake pedal or use the trailer hand-valve). A full trailer behind a truck Once you have coupled your rear trailer, you should test the coupling by?