Spring is the perfect season for a thorough fifth wheel cleaning and inspection.

During winter, cold temperatures may cause grease to thicken, which can bind moving parts and interfere with proper operation and timing of the various movements beneath the top plate. However, winter has one positive aspect: it’s wet and water is one of the best lubricants. With spring the roads dry out and so does the gunk under the fifth wheel, therefore we get more sticking and binding. It will be the perfect time for a cleaning and re-greasing.

Standard Preventive Maintenance on the fifth wheel should be performed every 90 days or 30,000 miles (whichever comes first), and it should include: cleaning, visual inspection, lubrication and checking the Wedge Stop Rod adjustment.

Inspect and adjust

You can’t do much of an inspection if the working parts are covered in gobs of grease, so a thorough cleaning must come first. Exact procedures may vary depending on the manufacturer, but essentially you need to check damages to the top plate, the release handle conditions, the slack in the jaws, and its proper function.

While adjustment procedures vary across brands and models, the amount of slack permissible does not. Roadside inspectors will sideline trucks with any more than half an inch of fore/aft movement between the top plate and the trailer, while the manufacturers recommend about 1/16-inch free play around the kingpin.

Maintenance & Repair Resources
Fontaine´s Fifth Wheels website features an extensive collection of how-to videos on inspections, maintenance and repair procedures, as well as technical training videos that offer certification upon completion.

Jost’s website boasts a live chat feature for product related inquiries. It includes product information, service bulletins, manuals and instructions for various services and repair procedures.

SAF Holland’s website contains a vast store of parts ordering references, maintenance and installation guides, and sales brochures.

Lubrication Recommendations

Properly lubricated fifth wheel top plates will retain peak performance for a long time. A layer of grease is essential for the free movement of the trailer and the tractor. When the fifth wheel has been cleaned up, apply a small bead of grease evenly in a back-and-forth motion. Apply a heavier coat to the rear two-thirds of the fifth wheel (the grease will be pushed forward when hooking up to a trailer). While different types of greases/oils can be used, greases formulated specifically for fifth wheel applications will provide the best lubrication.


Leave a Reply

Your email address will not be published. Required fields are marked *