Home > Common Errors

  • 855   What three methods can you use to secure a second trailer before coupl... Answer
  • 611   What is a converter dolly used for?... Answer
  • 533   On older vehicles there may be a lever, rather than a knob, for the tr... Answer
  • 483   To uncouple the converter dolly you should:... Answer
  • 482   When the emergency line loses pressure, what happens to the tractor pr... Answer
  • 441   To uncouple the converter dolly, you should:... Answer
  • 383   When coupling twin trailers, you should release the dolly brakes by:... Answer
  • 382   What happens when you push in the trailer air supply control knob and ... Answer
  • 373   To uncouple the converter dolly, you should:... Answer
  • 371   Which valves on the service line on the trailer connect the trailer ai... Answer
  • 368   The stopping distance for a tractor trailer traveling 55 mph on dry pa... Answer
  • 361   A drive-wheel skid when pulling doubles could result in a jackknife wh... Answer
  • 355   Which of these statements about seeing ahead is true?... Answer
  • 332   When coupling doubles, start by:... Answer
  • 300   What is one purpose of the emergency air line?... Answer
  • 298   Which valve keeps air in the tractor or truck if the trailer breaks aw... Answer
  • 286   When coupling the rear trailer, the correct trailer height is:... Answer
  • 281   The best way to stop all skids is to:... Answer
  • 269   To test the trailer service brakes you should:... Answer
  • 265   When inspecting doubles, the shut off valves at the rear of the traile... Answer
  • 262   Do all converter dollies have spring brakes?... Answer
  • 242   To connect the glad hands, the tow seals are pressed together with the... Answer
  • 239   If you want to couple a second trailer to your combination vehicle, se... Answer
  • 238   Inspect a converter dolly as if it were:... Answer
  • 236   Do trailers made before 1975 have spring brakes?... Answer
  • 220   You are doing a walk around inspection of a double or triple trailer r... Answer
  • 211   You should test your tractor protection valve to avoid:... Answer
  • 208   When can you use the trailer hand valve for parking a combination vehi... Answer
  • 207   Coupling and uncoupling methods are the same for more common tractor-t... Answer
  • 198   Which of these statements about managing space to the sides is true?... Answer
  • 197   To test the trailer service brakes, you should:... Answer
  • 196   To test the trailer service brakes you should:... Answer
  • 193   What are two reasons why doubles and triples take up more space than o... Answer
  • 191   Which of these is not a good thing to do when driving on slippery road... Answer
  • 182   The best way to keep brakes from overheating while going down a steep ... Answer
  • 175   When driving doubles or triples how whould they be driven to avoid rol... Answer
  • 167   What happens to the trailer emergency brakes if there is a loss of pre... Answer
  • 166   What is a reason why there is more chance of skids with doubles and tr... Answer
  • 164   What is it called when the rear wheels follow a different path than th... Answer
  • 159   When connecting the converter dolly to the rear trailer, you should re... Answer
  • 143   Which of these will result in the best control on curves?... Answer
  • 135   Should you unhook the pintle hook with the converter dolly still under... Answer
  • 129   You should use different methods for uncoupling second and third trail... Answer
  • 123   When steering to avoid a crash while pulling doubles, remember to:... Answer
  • 118   For the safest handling on the road when pulling doubles and triples, ... Answer
  • 117   Doubles and triples take up more space and are longer than other comme... Answer
  • 116   If the tractor protection valve closes, letting air out of the trailer... Answer
  • 114   If your trailer has started to skid, what should you do to get tractio... Answer
  • 106   To check for air flow to the last trailer:... Answer
  • 105   Which of these statements about handling of doubles and triples is tru... Answer
  • 99   In normal driving, should you ever use the trailer hand valve before t... Answer
  • 92   Why should you lock the glad hands to each other when you are not towi... Answer
  • 90   Which is true of empty trucks?... Answer
  • 87   If a converter dolly is still under the second trailer and you unlock ... Answer
  • 86   If the air lines on a truck are color coded, which lines are blue?... Answer
  • 86   When pulling triple trailers, always put the heaviest trailer:... Answer
  • 76   It is dangerous to unlock the pintle hook with the dolly still under t... Answer
  • 73   If the spring brakes do not release when you push the trailer air supp... Answer
  • 67   Doubles and triples are not as likely to turn over as are other combin... Answer
  • 49   In allowing more space, what should you do before entering or crossing... Answer
  • 49   It is alright to not check all the critical parts when doing a pretrip... Answer
  • 35   The dolly tow bar may fly up if you unlock the pintle hook with the co... Answer
  • 33   When pulling triple trailers, which unit is more likely to roll over:... Answer
  • 22   There are more things to inspect on a combination vehicle than on a si... Answer
  • 21   Special care should be taken when pulling two or three trailers becaus... Answer
  • 21   To uncouple double trailers, you should park your rig:... Answer
  • 20   When pulling triple trailers, which unit is more likely to roll over?... Answer
  • 17   You should do a walk around inspection when preparing to pull doubles ... Answer
  • 14   Is it important to be careful when driving doubles and triples?... Answer