How can you test that air flows to all trailers? D. Make sure the spare tire is secured, if it has one. 0000003261 00000 n Safety chains secured to trailer (s). If the dolly is a two axle unit then 1 Did you know you can fill out one quick form here on TruckingTruth and apply to several companies at once for paid CDL training? When driving a double or triple trailer, greater care must be given to. you are driving a 100ft truck eith double trailers at 50mph. How much space should be between the upper and lower fifth wheels? Make sure to visually inspect the fifth wheel and that the locking mechanism is You will speak with recruiters today. fifth wheel, so trailer is raised slightly when dolly is pushed under it. The A-dolly has a single drawbar with a single, centered hitching point. When you do this, you should hear: Which of these statements about emergency steering is true? How can you be sure you supplied air to a second trailer? How should you test the coupling? They are not only longer, but also need more space because they cannot be turned or stopped suddenly. B You should be sure the converter dolly air tank drain valves are ____ and the pintle hook is ____. There are more things that can go wrong, and doubles/triples are less stable than other commercial vehicles. For emergency braking you should: You are doing a walk around inspection of a double or triple trailer rig. We'll help you make the right choices and prepare for a great start to your trucking career. A converter dolly is If a converter dolly has spring brakes, you release the brakes by You have connected the converter dolly to the front semitrailer and then connected the rear semitrailer to the converter dolly. Connect the Converter Dolly to the Rear Trailer: Test the coupling by pulling against the pin of the second semitrailer. and possible answers include: open, free or closed, latched or closed, free or open, latched from TruckersDouble & Triple Trailer (CDL) Endorsement. Sometimes, metal tags are attached to the lines with the words service and emergency stamped on them. 0000004689 00000 n What is likely to happen? While doing a walkaround inspection of a double or triple, the converter dolly air tank drain valve should be _______, and the pintle hook should be _______. By using this site, you agree to be bound by our Terms of Use, Privacy Policy and Cookie Policy, Copyright 2000-2023 MH Sub I, LLC dba Internet Brands. Why should you pull a dolly out from under a trailer before you disconnect it from the trailer in front? A dolly has lights, air tanks, air relays, air lines, air brakes, ABS, electrical connections, etc. [California Commercial Driver Handbook] The weight of a truck: Is a major factor affecting stopping distance. The pressure in the service line is controlled by the brake pedal and the trailer hand brake. A. use a low gear Should the shut off valves on the rear of the first trailer be open or closed on a set of double trailers? What is one function of the tractor protection valve? A Open the emergency line shut-off valve at the rear of the last trailer. To do this without wheel chocks you should: When uncoupling the rear semitrailer, you should lower the converter dolly landing gear: When driving a double or triple, you need more space because they: Which of these statements about emergency steering is true? Which f these will result in the best control on curves? You must steer gently when pulling trailers. If there is a trailer B. you should avoid traveling next to others whenever possible The road is dry and the visibility is good. safe speed would be 40 MPH. coupled to the rear of a tractor-trailer combination forming a double bottom rig, A coupling device of one or two axles and a sixth wheel by which a semitrailer can be If the spring brakes do not release when you push the trailer air supply control, check the air line connections. 11 The air lines will rupture unsafe slow down even further, or better yet, find a safe haven and park until the The last trailer in a combination is most likely to turn over. We've all wondered if the adventure and challenges of life on the open road would suit us better than the ordinary day to day lives we've always known. Learn more and apply here: The more heavily loaded semitrailer should be in first position behind the tractor. Leave the emergency line shut-off valve closed and open the service line valve. The pressure in the service line tells how much pressure the relay valves should send to the trailer brakes. The road is dry and visibility is good. None of the above, 4. To do this without wheel chocks you should: Empty trucks: When parking your double or triple combination, you should look for a parking space D To check if the converter dolly is securely coupled to the rear trailer you should: Pull gently against the pin of the second trailer. The word part ferrit- means: D Closed, free, 8. first check for battery voltage to the valve by probing the wires of the electrical connector with a volt-meter it should be about 10.5 volts if not it's probably bad.next remove the valve. some large trucks have curved (convex or spot) mirrors. 3. You should keep at least ____ seconds of space ahead of you. B Each tank has a drain valve on it, and you should drain each tank every day. The converter dolly air tank drain valve on coupled double/triple trailers should be: Answer: Closed. Newer trailers have spring brakes just like trucks and truck tractors. Which of these statements about managing space to the sides is true? In order to receive your Doubles and Triples endorsement, it is required that you pass the states official CDL written Knowledge exam. When inspecting the air brakes on doubles and triples, you wait for air pressure to reach normal, then push in the red trailer air supply knob. When coupling twin trailers, a converter dolly is. Doubles/triples flip flop over from quick steering moves more easily than many vehicles. Safety fail-safe features of a tractor-trailer converter dolly. Question 4. . B. open; latched When driving a truck with more than one trailer, which trailer should be first behind the truck? Which of the following must be connected when coupling tractor to trailer or trailer to trailer? trailer << /Size 59 /Info 20 0 R /Root 22 0 R /Prev 29211 /ID[] >> startxref 0 %%EOF 22 0 obj << /Type /Catalog /Pages 19 0 R >> endobj 57 0 obj << /S 66 /Filter /FlateDecode /Length 58 0 R >> stream You should keep at least ____ seconds of space ahead of you. Any single vehicle with a GVWR of 26,001 or more pounds, or any such vehicle towing another not in excess of 10,000 pounds. securely fastened. A dolly should be pulled out from a rear trailer using? C. closed; unlatched, Which of these will result in the best control on a curve? C. may have poor traction due to bouncing and wheel lockup, Before you can supply air to the air tanks of a second trailer you need to: C View More Details. If there is In double and triple trailers, the trailer air supply control should pop or _________ when air pressure drops into the range of 20 to 45 psi. You must check that all shut-off valves are in the open position except the ones at the back of the last trailer, which must be closed. The crack the whip effect will topple the rear trailer first. A good and safe driver will always look out for ______. If a converter dolly is still under the second trailer and you unlock the pintle hook, what will probably happen? Open, free Charge the system and pump the brakes with the window down. Nothing will happen, but an in-cab warning indicator will let you know about the problem, It will cause the tractor protection valve to close and the trailer emergency brakes to come on, It will cause the tractor protection valve to open and the trailer emergency brakes to come on, When you try to put the service brakes on, air will quickly leak and will lower the air tank pressure, possibly activating the trailer emergency brakes, The emergency brakes will come on automatically as soon as a major leak occurs, Nothing, but braking power will be reduced, Air pressure will quickly leak away, even if you are not using the service brakes, Using a combination of the emergency air line and the service air line, Supply air will be sent to the service line instead of going to charge the trailer air tanks which means the trailer spring brakes will not release, Newer vehicles automatically detect if the lines are crossed and will auto-correct itself, Air will continue filling the air holding tanks until the tanks rupture from excessive pressure, Supply air will cause all brakes to release and the truck will roll freely without any braking ability, Trailers typically do not have their own air tanks, Designed to turn off the truck engine when a brake failure occurs, Used in the service and supply air lines at the back of trailers used to tow other trailers, Placed at each trailer spring brake and are designed to engage the emergency brakes when air pressure becomes too high, The yellow and red air control knobs located in the cab of a truck, Used to secure the trailer kingpin to the tractor 5th wheel, Caps which cover the valve stems on tires, A name for the yellow and red air valves in the cab of a truck, Coupling devices used to connect the service and emergency air lines from the truck or tractor to the trailer, Email Updates When New Articles Are Posted. When testing the coupling of the double trailer the landing gears of the rear trailer should be: You want to hook your combination to a second trailer that has no spring brakes. Driving doubles/triples is also more dangerous in hot and cold weather driving, as well as on mountain roads. You are doing a walkaround inspection of a double or triple trailer rig. 1/2 to 3/4 of an inch 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. Time used (Requires timer add on). A CDL is required to drive any of the following vehicles: A vehicle with two separate parts - the power unit (tractor) and the trailer. Take this same test in our other testing modes How to Get a Hazardous Materials Endorsement, What is a CDL? 0000005345 00000 n Make sure you can hear air escaping with the valve closed. The driver will be required to complete this requirement in three eight hour shifts. When connecting two trailers the converter dolly is connected to the rear trailer first. Open Check them all. A coupling device of one or two axles and a fifth wheel by which a semitrailer can be coupled to the rear of a tractor-trailer combination forming a double bottom rig Should the shut off valves on the rear of the first trailer be open or closed on a set of double trailers? The final procedure when connecting a rear trailer is to? Which of these is most likely to occur? When uncoupling, you should never unlock the _______ with the dolly still under the rear trailer. When inspecting doubles and triples you must make sure there is air all the way to the back of the last trailer, otherwise what may not work? Any trailer, 7. You shouldn't stop braking. B. are the easiest to stop since there is no shifting cargo When driving with more than one trailer, which trailer should be the first one behind the tractor? The trailer height is right when: The trailer will be raised slightly when the converter dolly is backed under it. rear brakes will not work properly. Use only the trailer brakes While inspecting your converter dolly coupling, you should make sure there is _____ between the upper and lower fifth wheel. Before you can supply air to the air tanks of a second trailer you need to. When entering a roundabout, a driver must yield the right-of-way to drivers already in the roundabout and obey all traffic signs. 7. A converter dolly is a piece of equipment designed to allow commercial trucks, such as semi-trucks, to pull a trailer. The shut off valves prevent air from going any further. You can find it here: High Road 2.0. Park on level ground, put chock on the tires, and charge the air tank. You should be sure the converter dolly air tank drain valves are _______ and the pintle hook is _____. Tractor-trailers are considered combination vehicles. If it goes low enough, the trailer emergency brakes will come on. Unless you are draining the condensation out of the air tank, then the drain valve Each trailer and converter dolly has one or more air tanks. The trailer brakes will unlock A sudden movement with the steering wheel can result in a tipping over rear trailer. a sudden movement with the steering wheel can result in a tipped over rear trailer, you wish to turn right from one two-lane, two-way street to another. A. use the engine brake or speed retarder A safe speed on a curve for a straight truck or a single trailer combination vehicle may be too fast for a set of doubles or triples. When does the "driver's manual" advise disconnecting the steering axle brakes to help Make sure you do not get in a spot you cannot pull straight through. you want to hook your combination to a second trailer that has no spring brakes. You should hear air escaping, showing the entire system is charged. Once that's complete, then its an easy push back and the 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. Some vehicles have dead end or dummy couplers to which the hoses may be attached when they are not in use. To check that the trailer emergency brakes are working properly, you should pull out the trailer air supply control and? C. drive through quickly, With the hand valve on, you should test the trailer brakes by opening the service valve line at the rear of the rig. Number of wrong answers. The driver must yield the right-of-way to other vehicles when merging and when entering a highway from an alley. Any items you have not completed will be marked incorrect. How do you know if your converter dolly is equipped with antilock brakes? On the first trailer in a set of doubles? The couplers have a rubber seal that prevents air from escaping. Safety chains should be secured to trailer(s). Pintle hook latched. Disconnect the glad-hand at the front of the first trailer and listen for air flow. Hit the article below to see specific information about AOBRDs! Use the dummy couplers when the air lines are not connected to a trailer. Why should you use chocks when parking a trailer without spring brakes? B What do you check when making a visual check of coupling? 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. Should I Be A Truck Driver? The converter dolly is an auxiliary axle with a coupling device.
the converter dolly air tank drain valve should be