Back in the fall of 2013, we ran a story in this column regarding the importance of regularly maintaining axle bearings. No, my memory isn’t good enough to really recall that we did this—I had to look it up. Still, the importance of regular bearing maintenance can’t be overstressed. Imagine rolling down the highway and seeing one of your trailer wheels go rolling past you in the fast lane. It happens!
We’ve had some comments from people who say they don’t like all the fooling around that bearing maintenance requires, so they’ve circumvented the problem by installing a special system that was designed for boat trailer owners. What they are talking about is a specially designed system that allows you to pump fresh grease into your axle bearings through a Zerk fitting—the kind you find on various lube spots on your car. The claim is that you’ll never have to pull the axle bearings apart to inspect them, and you’ve avoided a whole lot of extra labor.
As my father used to say, “Well, let me say this about that…”
First off, let’s address those lube systems designed for boat trailers. Boat trailers, by their nature of jumping into the water and back out again, have bearing systems designed to be sealed up not so with RV bearing systems. And a problem with just squirting grease into your bearings is simple—you don’t have a clue as to how much is already in there. If you pump in too much, what happens? What goes in, must come out, and the place it comes out is into the area of the backing plate—often times very close to your trailer brakes. Mixing axle grease with trailer brakes isn’t a good recipe for something you may need down the road—stopping power.
Not too long ago another outfit introduced an “easy” system specifically designed for RVers. The feedback from RVers who have used the system has been mixed, but on the cautionary side are things we’ve heard back. Among them, some complain they can’t pump enough grease into the system; still others are afraid they’ll blow the seals out. The manufacturer offers assurances that the design of the system won’t allow this to happen—that the old grease will flow back out near the grease gun nozzle, making it apparent when you’ve pumped in enough.
If this is so, perhaps concerns about “overloading” are unfounded. But here’s another issue: You’ll need to know what kind of grease you have in your system before you begin to pump in more in order to ensure that you are pumping in the same grease. Not all axle greases are compatible. Mix the wrong ones together and the results are like having no grease at all.
There’s one more thing to be said about saving time and effort. As one RVer says, “I figure those eight wheel bearings are supporting over 11,000 pounds of very valuable RV and equipment. One afternoon a year [to hand pack the bearings] is a small price to pay.”
Being forced to hand pack bearings means taking a good look at the bearings and other internal workings of the hubs—and an opportunity to catch problems before they move from the danger point to the disaster point.
Russ and Tiña De Maris are authors of RV Boondocking Basics—A Guide to Living Without Hookups, which covers a full range of dry camping topics. Visit icanrv.com for more information.