Fifth wheels are almost maintenance-free, but there are a few critical points to keeping them in good shape, according to the experts at Kenworth Truck Co.
First and foremost, think safety when you are inspecting your fifth wheel. There are several things that a driver can do:
• Keep the fifth wheel lubricated.
• Make sure that it is still connecting properly to the trailer.
• Verify that a sliding fifth wheel is locking properly.
• All of these can—and should—be done without touching the fifth wheel yourself.
The folks at Holland Hitch add the following recommendation before you start your inspection: have the entire fifth wheel system thoroughly steam-cleaned. Clean the top plate, brackets, slide plate, mounting angles and fasteners. Next, so that you can take a good look at the fifth wheel, use a trouble light or flashlight for your visual inspection. Plan to take 10 or 15 minutes for this project.
Test those jaws
Two people should be involved when examining fifth wheel jaws. Proceed as follows:
1. Latch the fifth wheel onto the trailer as usual.
2. Set the trailer brakes.
3. Have one person stand where he or she can see the fifth wheel.
4. Move the chassis back and forth slightly.
5. The assistant should watch to see if the plate moves relative to the trailer. If the plate does move, the jaws are probably worn. Head into the nearest dealership to have it checked by professionals.
To adjust the fifth wheel
Jost notes this is not something that usually needs to be done its their products, and in fact, frequent adjustments can cause premature wearing of the locking mechanism. Jost states it has many fifth wheels in service with over 400,000 miles on them that have not needed adjustment.
Fontaine says if it’s needed, its fifth wheels are easy to adjust—they can even be adjusted while the trailer is coupled to the fifth wheel if the situation calls for it.
SAF Holland provides manuals, as do the others, for those occasions when a fifth-wheel needs adjusting.
If you suspect this is the case, it should be checked by trained staff.
