949 When a tractor and a trailer are coupled, how much space should there ... Answer800 When inspect the coupling, you must make certain that there is enough ... Answer775 In what position should the air line shut off valves be when you check... Answer729 The air tanks on trailers and converter dollies are filled by:... Answer694 The emergency air line for:... Answer664 In order to supply air to the trailer, you must first:... Answer603 Which one of the following statements about tractor protection valves ... Answer595 The maximum air released when brakes are released is:... Answer578 The service air line is controlled by... Answer565 What is the emergency air line?... Answer536 For the coupling to be complete for a fifth wheel with a locking lever... Answer510 Why should you use chocks when parking a trailer without spring brakes... Answer483 Other names for the Service Air Lines are?... Answer480 You are driving a combination vehicle when the trailer brakes away, pu... Answer446 After applying brakes fully max on combination vehicles, what is the a... Answer444 If you cross connect the two air lines the following will result:... Answer438 What should the trailer height be before you connect a converter dolly... Answer431 The service line is for:... Answer420 Before you back under a semi-trailer in coupling your tractor at what ... Answer405 When you turn suddenly while pulling doubles, which trailer is most li... Answer393 Are fully loaded rigs more likely to roll over in a crash than empty r... Answer390 Why do large combination vehicles that are empty take longer to stop t... Answer369 The function of the trailer air supply control is:... Answer365 In order to inspect the coupling you should:... Answer357 A combination vehicle air brake system should not lose air faster than... Answer331 The trailer hand valve should be used:... Answer330 Coupling and uncoupling methods are the same for more common tractor-t... Answer328 You should swing wide to the left before starting a 90 degree turn:... Answer323 Which of the following statements about combination vehicles is true?... Answer323 When should you use the hand valve to park a combination vehicle?... Answer322 More than half of truck driver deaths in crashes are the result of tru... Answer296 Why should you check your mirrors whenever you apply the brakes hard?... Answer290 Why should you not use the trailer hand brake to straighten out a jack... Answer288 A device which connects the service and emergency air lines from the t... Answer285 To prevent rollovers, remember to:... Answer282 Off tracking is:... Answer280 What are some things that you can do to avoid getting surprised and ha... Answer280 When backing a tractor under a trailer, you should expect:... Answer272 When coupling the trailer, back up slowly until:... Answer268 If you start a trailer skid, you should:... Answer266 When coupling the glad hands, you should NOT do the following:... Answer261 You have connected the air lines but have not yet backed under the tra... Answer259 Semi trailers made before 1975 that are equipped with air brakes:... Answer254 Large combination vehicles take longer to stop:... Answer254 Since a sudden movement with your steering wheel can tip a trailer ove... Answer230 What tells how much pressure the relay valves should send to the trail... Answer228 Which is true when rolling up the landing gear to complete the couplin... Answer227 A trailer jackknife is:... Answer226 What two things can a driver do to prevent rollovers?... Answer225 The earliest way to notice a trailer skid is:... Answer223 You should use different methods for uncoupling second and third trail... Answer214 After you lock the kingpin into the fifth wheel how can you check the ... Answer212 Which one of the following is controlled by the foot brake?... Answer212 You should crank the landing gear until:... Answer207 When traveling under 40 mph, you should follow other vehicles:... Answer206 You should not back a tractor under a trailer until the whole air syst... Answer200 You have coupled with a semi trailer. In what position should you put ... Answer192 Before you back under the trailer, you should be sure that the trailer... Answer186 Before driving away, how can you always test the trailer brakes?... Answer183 If you will be pulling doubles where one trailer is more heavily loade... Answer181 Why should you lock the tractor gland hands (or dummy couplers) to eac... Answer175 The fifth wheel locking lever is not locked after the jaws close aroun... Answer170 You should not use the trailer hand valve while driving because:... Answer163 What happens if (only) the service line comes apart while you are driv... Answer154 Which amount should a combination vehicle NOT lost air faster than?... Answer148 The fifth wheel should be checked to see if:... Answer147 When you make a quick lane change, the trailer only may overturn. What... Answer147 When you get ready to back under the semi trailer you should line up:... Answer145 Offtracking occurs when you go around a corner and:... Answer139 Why must the fifth wheel plate have enough grease?... Answer132 The following two things will help prevent rollovers.... Answer132 Why must you be extra careful when bobtailing?... Answer125 Why should you never unlock the pintle hook with the dolly still under... Answer124 Looking into the back of the fifth wheel, which part of the kingpin sh... Answer123 The trailer air supply control:... Answer120 What is the cause of more than half the truck driver deaths in crashes... Answer118 After you have coupled the tractor with a trailer where should the lan... Answer106 If you start a trailer skid, you should:... Answer101 Before backing up how should you position the tractor in relation to t... Answer95 Which is true regarding the trailer air supply control?... Answer93 The dolly tow bar may fly up if you unlock the pintle hook with the co... Answer84 After you lock the kingpin into the fifth wheel how can you check the ... Answer79 A kingpin is:... Answer71 When the wheels of a trailer lock up, what will the trailer tend to do... Answer60 There are two things that a driver can do to prevent a roll over. They... Answer53 Combination vehicles are usually heavier, longer and require more driv... Answer52 What should you use to be safe when you park trailers that don't have ... Answer42 There are more things to inspect on a combination vehicle than on a si... Answer26 You should do a walk around inspection when preparing to pull Doubles ... Answer |