Maintaining the underside of your is less fun than washing and waxing the top side, but contributes the most to the trailer’s trouble-free operation over the years. This includes tire maintenance and inspecting and repacking bearings.
Tire maintenance is simple. If your trailer uses regular trailer tires, keep them inflated to at least twenty-five pounds of air. Trailer tires are rated to handle up to fifty pounds of air pressure, but you’ll never need to maintain that much. A lower pressure will provide some additional cushion for the contents of your trailer without significantly shortening the life of the tires. Inspect your tires at the beginning of the riding season for signs of deterioration or embedded objects. While you’re on the road, check trailer tire pressure when you check your bike’s tires.
Unless you travel tens of thousands of miles each year with your trailer, you will probably never wear them out. Its more likely that you’ll need to replace your tires after a few years due to exposure to UV rays. Over time tire rubber loses the natural oils that make it, well, rubbery. This leads to cracks in the sidewall. The tread of the tire may become noticeably hardened, much like an old pencil eraser. In either case, these tires should be replaced. Standard size trailer tires are available at many locations in the U.S. including Wal-Mart and any RV or trailer dealer.