Contents
- 1 When you are uncoupling a trailer you should?
- 2 What is the correct order of steps for uncoupling double trailers?
- 3 What is done before uncoupling an air ride tractor from the trailer?
- 4 How should you align your tractor to a trailer when preparing to couple?
- 5 What might happen if the trailer is too high?
- 6 What should you do to stop a trailer skid?
- 7 What three methods can you use to secure a second trailer before coupling?
- 8 How can you be sure you supplied air to a second trailer?
- 9 Which shutoff valves should be open and closed?
- 10 What does coupling mean in trucking?
- 11 What is high hooking?
- 12 When you get ready to back under the semi trailer you should line up?
- 13 When the trailer is lying flat on the fifth wheel how much gap space is acceptable?
- 14 What gear should the tractor engine be in after you uncouple the trailer and are inspecting the trailer supports?
When you are uncoupling a trailer you should?
The following steps will help you to uncouple safely.
- STEP 1: Position Rig.
- STEP 2: Ease Pressure on Locking Jaws.
- STEP 3: Chock Trailer Wheels.
- STEP 4: Lower the Landing Gear.
- STEP 5: Disconnect Air Lines and Electrical Cable.
- STEP 6: Unlock Fifth Wheel.
- STEP 7: Pull Tractor Partially Clear of Trailer.
- STEP 8: Secure Tractor.
What is the correct order of steps for uncoupling double trailers?
6.3 Coupling and Uncoupling
- STEP 1: Inspect Fifth Wheel. Check for damaged/missing parts.
- STEP 2: Inspect Area and Chock Wheels.
- STEP 3: Position Tractor.
- STEP 4: Back Slowly.
- STEP 5: Secure Tractor.
- STEP 6: Check Trailer Height.
- STEP 7: Connect Air Lines to Trailer.
- STEP 8: Supply Air to Trailer.
What is done before uncoupling an air ride tractor from the trailer?
Before dumping the tractor’s air ride suspension, move the truck forward slightly to disengage the king pin from the 5th wheel jaws. If the 5thwheel “hangs up” on the king pin, it could damage both the king pin and the 5th wheel coupling mechanism.
How should you align your tractor to a trailer when preparing to couple?
Put the tractor directly in front of the trailer. (Never back under the trailer at an angle because you might push the trailer sideways and break the landing gear.) Check position, using outside mirrors, by looking down both sides of the trailer.
What might happen if the trailer is too high?
What might happen if the trailer is too high when you try to couple? If the trailer is too low, the tractor may stike and damage the trailer nose; if the trailer is too high, it may not couple correctly. If there is space something is wrong and the trailer would come loose very easily.
What should you do to stop a trailer skid?
What is the first thing you should do to prevent a trailer skid? Step on the brakes hard several times to stop the skid. Recognize that a skid has started to occur in the mirrors. Use the trailer hand brake.
What three methods can you use to secure a second trailer before coupling?
What three methods can you use to secure a second trailer before coupling? Release dolly brake by opening the air tank petcock or if the dolly has spring brake, use the dolly parking brake control. Wheel the dolly into position by hand so it is in line with the kingpin.
How can you be sure you supplied air to a second trailer?
How can you be sure you supplied air to a second trailer? You should check the height of the trailer before connecting a converter dolly to a second or third trailer. The trailer height is right when: The trailer will be raised slightly when the converter dolly is backed under it.
Which shutoff valves should be open and closed?
If you’re only pulling one trailer, the shut off valves should always be closed or else the air will simply escape out the back of the trailer. If you’re pulling more than one trailer, all valves should be open except the very last trailer, which should have all valves in the closed position.
What does coupling mean in trucking?
The fifth-wheel coupling provides the link between a semi-trailer and the towing truck, tractor unit, leading trailer or dolly. To reduce friction, grease is applied to the surface of the fifth wheel.
What is high hooking?
High hooking happens when the kingpin on the trailer is higher than the fifth wheel. Since the fifth wheel pivots on a horizontal axis, the kingpin will hit the fifth wheel, slide across the top, and come to a rest in front of the fifth wheel. Hooking a trailer to a big truck is not hard to do.
When you get ready to back under the semi trailer you should line up?
4. When you get ready to back under the semi trailer you should line up: A About 12 degrees off the line of the trailer.
When the trailer is lying flat on the fifth wheel how much gap space is acceptable?
b. No gap is permissible between the trailer upper coupler plate and the fifth wheel. (6.35 mm) or less gap visible between the lock jaws.
What gear should the tractor engine be in after you uncouple the trailer and are inspecting the trailer supports?
CDL
| Question | Answer |
|---|---|
| What gear should the tractor engine be in after you uncouple the trailer and are inspecting the trailer supports? | Neutral |
| You have coupled with a semitrailer. Where should you put the iron trailer supports before driving away? | Fully raised with the crank handle secured in its bracket. |
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