The rest of the axels on the vehicle are nearly the same as the front steer axels, with a few differences. What are the differences?
A. Torsion bar, treads, and air bags
B. Torsion bar, treads, space between the tires or spacers, and air bags
C. Tread depth, space between the tires or spacers, and air bags
D. Torsion bar, space between the tires or spacers, and air bags
There are FOUR differences between the steer axel, and the tractor and trailer axels. They are the Torsion bar, the space between the axels so bud rims or spacers, tread depth changes from four thirty seconds to two thirty seconds, and retreads are allowed on every axel but the steer axel, and the air bags portion of the suspension.
2 / 10
The apron is the metal plate welded on the bottom of the trailer that gives the 5th wheel a smooth surface for vehicle connection. What should you check the apron for?
A. That it is not bent, damaged, or cracked, has no illegal welds, and that it is securely mounted
B. That it is not bent, damaged, cracked, and that it is securely mounted
C. That it is not bent, damaged, or cracked
D. That it is not bent, and that it is securely mounted
The apron itself should not be bent, cracked, or damaged. It will be welded to the bottom of the trailer, but it should not have welds on the surface that the 5th wheel contacts, and it should be securely mounted.
3 / 10
The kingpin is a cylindric piece of metal protruding down from the apron, it has a base which is near the apron, shank or the narrow section of the kingpin where the locking jaws connect, and the head or the part furthest from the apron. What should you check the kingpin for?
A. Securely mounted, not bent or damaged, no cracks, and no illegal welds
B. Not bent or damaged, no cracks, and no illegal welds
C. Securely mounted, no cracks, and no illegal welds
D. Securely mounted, not bent or damaged, and no cracks
The kingpin is part of what holds the tractor and trailer together, it needs to be straight with no damage. You should not have any cracks in the metal, and there should not be any welds on the visible portion of the kingpin.
4 / 10
The 5th wheel is mounted on the back of the tractor, it lifts the trailer slightly when it contacts the apron when you are coupling the vehicles, and it houses the locking jaws which wrap around the shank of the kingpin to securely attach the trailer. True or False: The 5th wheel should be greased, no illegal welds, not damaged, and tilt with enough pressure.
A. False
B. True
This is true. The 5th wheel tilts so that the coupling can withstand unlevel surfaces, it cannot have welds or cracks, and needs to be secure.
5 / 10
You should check to make sure that the locking jaws are completely wrapped around the shank of the kingpin during your pre-trip inspection?
A. False
B. True
This is true. The kingpin needs to be completely extended and around the shank of the kingpin.
6 / 10
When coupled there should be a slight gap between the 5th wheel and the apron, meaning you should be able to see light between the two.
A. True
B. False
To have a properly connected vehicle there can be no gap between the 5th wheel and the apron. If there is a gap you should disconnect the tractor, lower the front of trailer, and recouple the tractor. A gap could mean the locking jaws went around the head of the kingpin instead of the shank. This is dangerous because a large bump may cause the trailer to lift, and the kingpin to slide out of the locking jaws.
7 / 10
The 5th wheel has a release arm built into the side of it, it automatically locks the jaws around the kingpin when you connect the vehicles, but it can be pulled out to release the locking jaws for uncoupling. What is the correct position of the release arm when the vehicle is coupled?
A. completely in with the locking mechanism secured
B. completely in with the locking mechanism released
C. completely out with the locking mechanism released
D. completely out with the locking mechanism secured
The release arm needs to be pushed completely in with the locking mechanism secured. You want to make sure this is secure because if it is not the trailer might break free of the locking jaws.
8 / 10
Most 5th wheels are adjustable for weight distribution and turn clearance, these are called sliding 5th wheels, they have a release are that needs to be completely in and locked, and a locking mechanism. What locks the 5th wheel in place?
A. Locking pins
B. Air
C. Locking jaws
D. Springs
Locking pins extend through holes in the platform to lock the sliding 5th wheel in place.
9 / 10
The 5th wheel platform needs to be checked for?
A. Tight and secure, properly mounted, all the bolts are in place and secure, not excessively damaged, and there are no illegal welds
B. Tight and secure, properly mounted, and there are no illegal welds
C. Tight and secure, properly mounted, and all the bolts are in place and secure
D. Tight and secure, all the bolts are in place and secure, and there are no illegal welds
The platform needs to be free of illegal welds, be tight and secure, properly mounted, not damaged, and all bolts need to be in place and secure.
10 / 10
At the rear of the tractor there are still a few things to check, what are they?
A. ICC bumper, mud flaps, light lens covers, and reflectors
B. Mud flaps, light lens covers, and reflectors
C. Mud flaps, air lines, and ICC bumper
D. Air lines, ICC bumper, and reflectors
The only things you needed to check at the rear of the tractor are the light lens covers, reflectors, and the mud flaps.
