Special precautions ought to be taken during cold weather to ensure continued proper operation of truck fifthwheels, advocates fifthwheel manufacturer Fontaine International. The reason being, in low temperatures, many lubricants become thick and binding, plus ice and sludge can build up on the underside of fifthwheel plates.
“As a result, parts may get stuck or move sluggishly, making the fifthwheel difficult to operate,” said Fontaine International's Terry Mennen. “The jaw and wedge may even be prevented from closing properly.”
In preparation for winter weather, the company recommends thoroughly cleaning the fifthwheel latching mechanism using a suitable cleaner or degreaser to ensure that all parts can travel freely. Grease and road grime also should be removed from the slider mechanism of fifthwheels equipped with sliders.
If temperatures are already consistently below freezing, and the fifthwheel suffers from a large buildup of grease and grime, Fontaine advises a complete steam cleaning.
Once the fifthwheel is clean, it should be thoroughly lubricated, and the jaw and wedge greased on the top and bottom. To do this, the company says separate the jaw and wedge with a large screwdriver and distribute the grease along the full length of the mating surfaces. Open and close the fifthwheel several times to further distribute the grease.
It suggests using a Moly-based lubricant such as Mobilgrease Moly 50 or equivalent when applying lubricant for cold weather. Equipment that is driven in regions with extreme and/or prolonged freezing temperatures may benefit from lubrication with a less viscous substance, such as 90-weight oil, to help ensure the proper movement of the latching mechanism.
Before mixing lubricants, Fontaine recommends contacting the lubricant manufacturer for guidelines on compatibility.
Videos, technical bulletins, and instruction handbooks for all necessary maintenance and repair of Fontaine fifthwheels are available at no charge by calling (800) 874-9780.