Trailer Troubleshooting

By Tim Murphy and Mark Corke

Taking care of your trailer is simple stuff, but ignore the basics and the trailer could leave you stranded.

Trailer bed

We've put together a few tips to help you have a happy, and hopefully, trouble free trailering experience. Many boaters lavish care and attention on the boat, but give little time or thought about looking after the trailer, that is until it breaks down. Hopefully you'll find the tips and other information here useful which will prevent you calling for a tow. We've included links too, where you'll be able to find more resources online. Don't forget that there is a ton of information available on our website written by some of the most knowledgeable folks in the business.

Not all tires are created equal. Before replacing the tires on your trailer, ensure that you buy the correct type. Tires should be stamped with an "ST" classification, for "special trailer." Dedicated trailer tires are more durable and resist abrasion and impact better than passenger "P" tires or light-truck "LT" tires; they also bounce less. Make sure the tire is neither overinflated nor underinflated and that the weight on the trailer doesn't exceed its capacity. To learn more about trailer tires go to "11 Things To Know About Boat Trailer Tires".

Trailers should never be overloaded. Check the maker's identification plate, which is normally fixed on the left side near the hitch, for maximum gross weight. It's also a good idea to make a note of the VIN (vehicle identification number) at the same time, which may help in recovering your trailer if it's ever lost or stolen. Learn more about VIN numbers see "Buying A Used Trailer?"

A major cause of breakdown is failure of trailer wheel bearings. After you've been driving for a few miles, pull over at the side of the road and carefully put your hand on each wheel hub in turn. If one hub is noticeably hotter than the others, this could be a sign that the wheel bearings are on the way out. It could also indicate a dragging brake — most noticeable with drum brakes. Wheel hubs that overheat will often drive grease out of the bearing, causing them to seize up and should be attended to without delay.

Consider letting wheel bearings cool before dunking them into water. When you immerse that heated wheel assembly in cold water, the temperature drop causes a vacuum inside the hub, which draws gritty seawater into the wheel assembly; damage to metal parts can follow swiftly. For this reason, bearings should be carefully inspected, cleaned, and repacked with grease annually. A bearing protector, such as those made by Bearing Buddy, solves the problem of launch-time vacuum pressure. A fitting replaces the normal hub dust cap and allows you to pump grease at positive pressure into the assembly. Frequently launched trailers should have them. For tips and advice on bearing protectors, see "Keeping Your Trailer Tire Bearings Happy".

Trailer wheel bearings should be examined seasonally, or every 2,000 miles, and repacked with grease. Check out the link shown below to see how to do this yourself. It's not that complicated a job provided that you have a decent tool kit. How do you check, inspect, and replace wheel bearings? See "12 Steps To Repacking Or Replacing Your Bearings".

Trailer tires in salt water

If launching your boat into saltwater rinse off the trailer with clean freshwater right away, if you can. Saltwater is very corrosive and will corrode brakes, bearings, and other trailer components in addition to the trailer chassis. See "How To Wash A Trailer".

Brake pads are a routine-wear item. Follow the manufacturer's instructions for indications of when it's time for replacement. Brake lines are another regular service item. Fluid levels should match the manufacturer's recommendation; if they call for, say, new "DOT 3 brake fluid," don't substitute anything else. Seals and other components depend on the right blend; using the wrong sort may damage seals and could be dangerous by causing brakes to fail, often under hard braking — just when they are needed the most. If brake lines need to be replaced or bled, carefully follow the manufacturer's instructions. Learn about trailer brakes at see "Give Me A Brake" and "The Lowdown On Trailer Brakes".

Trailer tires tend to get ignored over the winter, so check them carefully before setting off on a journey. Make sure that tires aren't unduly worn and have at least and eighth of an inch of tread left on them. Look too for cracks in the sidewall, bulges, or ridges. Finally, make sure they are correctly inflated — trailer tires are often inflated to higher pressures than the towing vehicle's tires. For extra info on looking after trailer tires, see "Tires: Where Rubber Meets The Road". 

— Published: Spring 2016


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