There are 2 major brands of fifth wheels used in the industry today. Both accomplish exactly the same function, but the methods are not exactly the same, and the care of each is also quite different.
A visual check of the fifth wheel is all that is needed to determine which brand of fifth wheel you have. Fontaine fifth wheels have a squared off front, which is smooth all across, whereas the Holland fifth wheel is more rounded, and will have a bolt with a nut protruding through the front of the fifth wheel plate. As a driver, fifth wheels are virtually maintenance-free, but you do have to keep an eye on them, as they can and do fail from time to time.
To determine if a Fontaine fifth wheel is properly locked around the king pin, first check the release handle. It should be about 1 inch from the body of the fifth wheel. Next, crawl under the trailer and with a flashlight, look into the throat of the fifth wheel to visually ensure the jaws are fully locked around the king pin. If everything appears to be in order, finish hooking up to the trailer, but only raise the landing gear about 2 inches from the ground. Back in the truck, try pulling against the trailer parking brakes while watching in your mirror to see if the truck pulls away from the trailer. If it does, then you’re not properly connected. If it doesn’t, supply the trailer with air to release the parking brakes. Once the trailer brakes release, start to roll forward slowly, and use the spike to apply the trailer brakes only. If everything comes to a complete stop, you are properly hooked to the trailer, and you can crank the landing gear all the way up.
Some drivers have reported a maintenance issue regarding Fontaine fifth wheels. Before applying fresh grease, scrape as much of the old grease off as you can, especially in the throat of the fifth wheel, and around the locking jaws. Apparently, excess grease can gum up the workings, and even though the fifth wheel passes both visual checks and both tug test, it could come unlocked and cause the trailer to fall off. There have been reports of drivers travelling over 100 miles before the fifth wheel fails, so it’s a good idea to visually check the fifth wheel lock every couple of hours, especially in the colder winter months.
