- Not really matter much
- Be low enough so that it is raised slightly when the tractor is backed under it
- Be high enough so that the tractor completely clears it when backed under it
- Be low enough to require high RPM's to back under it
From The CDL Manual
The trailer should be low enough that it is raised slightly by the tractor when the tractor is backed under it. Raise or lower the trailer as needed. (If the trailer is too low, the tractor may strike and damage the nose of the trailer; if the trailer is too high, it may not couple correctly.)
- Should be supported out of the way
- Should be disconnected
- Should be left dangling
- Should generally be ignored
From The CDL Manual
STEP 7: Connect Air Lines to Trailer
- Check glad hand seals and connect tractor emergency air line to trailer emergency glad hand.
- Check glad hand seals and connect tractor service air line to trailer service glad hand.
- Make sure air lines are safely supported where they will not be crushed or caught while tractor is backing under the trailer.
- Listen for the sound of trailer brakes being applied and released
- These are all steps to be sure that the air lines are connected properly
- Check air pressure gauge for signs of major air loss
- Turn off the engine so you can hear the brakes
From The CDL Manual
Check brake system for crossed air lines.
- Shut off engine so you can hear the brakes.
- Apply and release trailer brakes and listen for sound of trailer brakes being applied and released. You should hear the brakes move when applied and air escape when the brakes are released.
- Check air brake system pressure gauge for signs of major air loss.
- After kingpin locks, push trailer back a few feet
- Use lowest reverse gear
- Stop when kingpin locks into the fifth wheel
- Back under trailer slowly
From The CDL Manual
STEP 10: Back Under Trailer
- Use lowest reverse gear.
- Back tractor slowly under trailer to avoid hitting the kingpin too hard.
- Stop when the kingpin is locked into the fifth wheel.
- Putting hazard flashers on
- Putting parking brakes on
- Wedging something against the brake pedal
- Sounding the air horn twice
From The CDL Manual
STEP 12: Secure Vehicle
- Put transmission in neutral.
- Put parking brakes on.
- Shut off engine and take key with you so someone else will not move truck while you are under it.
- It doesn't matter
- 2 inches
- 1 inch
- None
From The CDL Manual
Make sure there is no space between upper and lower fifth wheel. If there is space, something is wrong (kingpin may be on top of closed fifth wheel jaws; trailer would come loose very easily).
- Ensure that the safety latch is in position
- Make sure the fifth wheel jaws are closed around the kingpin
- Make sure that there is space between the upper and lower fifth wheel
- Make sure the locking lever is in the "lock" position
From The CDL Manual
STEP 13: Inspect Coupling
- Use a flashlight if necessary.
- Make sure there is no space between upper and lower fifth wheel. If there is space, something is wrong (kingpin may be on top of closed fifth wheel jaws; trailer would come loose very easily).
- Go under trailer and look into the back of the fifth wheel. Make sure the fifth wheel jaws have closed around the shank of the kingpin (see Figure 6-7 on page 76).
- Check that locking lever is in the “lock” position.
- Check that safety latch is in position over locking lever. (On some fifth wheels, the latch must be put in place by hand.)
- If the coupling is not right, do not drive the coupled unit; get it repaired.
- Be sure air lines are away from all moving parts of the vehicle
- These are all important points of the inspection
- Plug electrical cord into trailer and fasten safety latch
- Electrical and air lines should be checked for damage
From The CDL Manual
STEP 14: Connect the Electrical Cord and Check Air Lines
- Plug the electrical cord into the trailer and fasten the safety latch.
- Check both air lines and electrical line for signs of damage.
- Make sure air and electrical lines will not hit any moving parts of vehicle.
- Should be fully raised before moving
- Should be removed before driving
- Should just barely clear the ground when driving
- Should be raised halfway up before driving
From The CDL Manual
Raise landing gear all the way up. (Never drive with landing gear only part way up, as it may catch on railroad tracks or other things.)
- Is on an incline
- Has other trucks parked on it
- Is protected from the elements
- Can support the weight of the trailer
From The CDL Manual
STEP 1: Position Rig
Make sure surface of parking area can support weight of trailer
Have tractor lined up with the trailer. (Pulling out at an angle can damage landing gear.)