Big Pete was one of the founding members of the Herd of Turtles, a Perth based 4WD enthusiasts society. Big Pete has many years experience both behind the wheel and under the vehicle, being involved in 4WD driver training and custom engineering. You can visit the Turtles site [here]

Big Petes Trailer Maintenance Tips

The most common maintenance item on a trailer as everyone knows are the bearings. If the wheels don’t turn you’re not going anywhere. I suggest that at least once a year to completely disassemble the hubs and thoroughly clean and inspect the bearings. You can use any type of solvent you want kero or petrol work really well.. As you clean the bearings, look for any obvious wear marks, pits, or gouges where a piece of dirt might have gotten caught in the needle bearings. The needle bearings themselves should be completely smooth with little wear. Next, clean the hub itself completely. then inspect the races inside the hub. More often than not the races will tell the full story of the condition of the bearings. The races should be mirror smooth with no marks at all. If there is a groove, pit, or even a water mark on the race, replace it. Always replace your hub seal when you inspect your bearings. For the couple of bucks it costs, it will be well worth it. And for boat trailers, use nothing but a double lip seal. This type of seal has a little spring on the rubber part and keeps tension on the seal to aid in keeping water out of the hub.

While you have your hubs and wheels off now is a good time to check your springs, axle, and other suspension bits. There should be no scaly rust on the springs and the leaves of the springs should be sandwiched tightly together. The axle should not be bent (duh!) Or have an abnormal amount of rust. The one item that should not be overlooked on the axle is the place where the hub seal rides. This area should be completely smooth no rust pits or grooves. If the seal does not fit tightly around this part of the axle, you can expect nothing but problems. If you do find that you need to replace your axle, it would be worth your while to search for a type of axle that has a grease fitting on the end of the spindle itself. This eliminates the need for any other type of lubrication device like bearing buddies. In my opinion, this is the best type of axle you can buy. With bearing buddies, only the outside bearing gets any grease. Bearing Buddies are better than having nothing at all but caution must be used not to over grease and blow out the rear seal. If you are slinging grease on the insides of your trailer wheels it is time to replace your hub seals and quite possibly your bearings and races. 

One avoidable problem when towing boats or heavy camper trailers and vans, has to do with tire wear. Many people think they have a bent axle because of bad tire wear. 9 out of 10 people that have abnormal tire wear is simply due to low tire pressure. Most trailer tyres carry their max rating at full pressure. What most people don’t realize is that max pressure on a trailer tire is usually around 50 psi. not 35 psi. like car tires. Some large trailer tyres carry max ratings of 90psi.!!! Always check tire pressures before you go out on a long trip. The sidewall on most trailer tires are not as stiff as passenger car tires and will overheat very quickly when underinflated which could lead to a blowout. Not much fun in the middle of nowhere.
 
On long trips, I would suggest to bring along spares of everything you can think of. This would include a whole hub assembly, a spare tyre, spring?(you never know, stranger things have happened), u-bolt kit to attach the axle to the springs, and anything else you can think of that might wear out or break   The old adage is true "If anything can go wrong, it will.

If your trailer is equipped with brakes, they, just like those on your car, require maintenance. Most trailers are equipped with hydraulic surge brake systems or electric systems,hydraulic systems use a coupler or actuator. When you hit the brakes the trailer "surges" toward the tow vehicle telescoping the actuator to apply force to its master cylinder, which then applies hydraulic pressure to the trailer brakes.

The actuator has a reservoir of brake fluid that needs to maintain a certain level to be effective. Check it regularly. Occasionally the interior components of the actuator or coupler need to be serviced by a knowledgeable mechanic to ensure proper operation.

Electric brakes require a brake controller to apply power to the brake system. With electric brakes, as power is applied to the electromagnets in the brake cluster, the magnets are pulled to the interior flat surface of the hub drum. As the wheel and drum turn during travel, this attraction of the magnet to the flat drum face pulls the lever arm of the brake actuating cam, rotating the cam and forcing the brake shoes out to contact the drum braking surface. The more power applied to the magnets the greater the leverage on the cam resulting in greater braking response.

Brake lines should also be checked for fray, leaks and loose fasteners.

Attention should also be given to the trailer's electrical system by inspecting the wires, connections globes and lenses. Putting a little grease on light bulb bases and plug contacts will help prevent rust and corrosion. It is important to periodically check the system's earth wire to make sure it's securely attached to the trailer.
If you have a boat trailer or a winch for flip over floor campers, the trailer winch gears should be oiled occasionally. Inspect the lock spring to make sure it works properly and hasn't corroded. Check out the winch strap or cable for fray or kinks and replace it if it looks bad.

Rollers and skids are also something that needs to be looked at if they are not in good condition you run a very big risk of damaging the hull of your boat

All of this may sound like a lot of work, but in reality it doesn't take as long as it may appear. And doing it regularly helps ensure that your trailering experience will be fun—which, incidentally, is a three-letter word