8 easy ways to maintain your boat trailer

RACV Marine

Boat trailer up close

Trailers are an integral part of every trailerboat rig, yet they often command little interest from their owners — until something goes wrong.

Trailers break down for all sorts of reasons, but more often than not the culprits are flat tyres, poorly maintained brakes and corrosion. A trailer problem is at the very least extremely inconvenient, as it can immobilise your boat, and at worst life-threatening, if something goes wrong while you’re towing at speed on the freeway.

It always pays to have an emergency backup which is why RACV Marine offers Emergency Roadside Assistance for boat trailers and tow vehicles. While we genuinely hope you don’t get stranded, different packages are available to cover your style of boating in the event of an emergency. Call 13 11 11 and we’ll help get it sorted.

The best way to not get stranded, of course, is to prevent problems from occurring in the first place — and the best way to go about that is with simple and routine trailer maintenance. Here are some tips to get you started.

Have the right trailer

It may sound obvious, but it’s vital to have the appropriate trailer for your boat. Yes, the trailer is not the source of on-water enjoyment — it’s merely a means to an end — but while the temptation may be to get the smallest and cheapest, second-hand trailer imaginable, it may not be worth the risk. A non-compliant trailer (i.e. one that’s illegal) is a danger to you, your boat and other drivers, and the authorities will take a dim view if you’re towing a boat on one and are involved in an accident.

Thankfully, the rules on trailer compliance, braking requirements and loads are pretty clear.

Cleaning your boat

Always wash down to prevent corrosion

Salt water is inherently corrosive — and corrosion is fatal to steel trailers. Or rather, it will be, if you don’t wash down after every outing.

On steel trailers, rust has a nasty tendency to appear in inaccessible spaces. Regular checks of all components will flag problems before they spread so make a point of regularly inspecting your trailer, paying close attention to bolts, joins and welds. Any sign of cracking should be immediately addressed. Similarly, all rearward components (the end that gets dipped in the water) should be closely scrutinised.

If possible, have the trailer on a jack so you can look underneath. Don’t forget to look inside and around all components like brakes and calipers.

Aluminium trailers are significantly more resistant to corrosion than traditional steel trailers. However, they still require maintenance, and pay close attention for possible cracking.

Rollers and runners can stick or degrade due to salt and sand. Again, always give them a good rinse and replace if excessive wear is visible. If wear is more prominent on one side, then the rollers may need adjusting.

Check the tyres

Tyre problems are one of the most common causes of trailer breakdowns, so make a habit of checking your tyres before heading out.

Tell-tale signs include worn or irregular tread, deformed sidewalls or bulging. Cracking may be a symptom of dry rot. Look out for tyre abnormalities if the trailer has emerged from sitting idle during winter. Occasionally moving it over this period helps.

Check air pressure and inflate as per the manufacturer’s recommendations. Make sure that tyre rims are in good order too, as a deformed rim could in some cases lead to a blowout.

Check wheel bearings

Maintaining and replacing wheel bearings can add years to a trailer’s life. And yet, lack of maintenance is one of most common causes of trailer failure.

Trailer wheel bearings should be checked at least once a year (and ideally more often). Remove the bearings and thoroughly inspect them for wear. If there is heat damage, this will show as a blue tinge.

If you have any doubt, remove and replace the bearings. Otherwise, clean them so that they’re free of dirt and water, re-pack with grease and re-seal. Once everything is re-assembled, turn the wheels and look for ‘unnatural’ movement and listen for any noise. The wheel should turn without squeaking, while rocking and wobbling implies that the bearing may need tightening. While you’re at it, give the axle shaft(s) a good going over with grease.

Boat being pulled on trailer

Suspension and axles

Leaf spring suspension has been around for many decades and remains a highly popular boat trailer option because of its simplicity and reliability. As with other trailer components, suspension can corrode. Rusted leaf springs on their way out will begin to spread and lose their integrity. Note that some superficial rust is to be expected, so don’t freak out just yet. Cracks and chunks coming off, however, are cause for concern, particularly if this is evident on the U-bolts.

Rubber torsion suspension systems tend to be more sophisticated. Again, they are subject to corrosion like any other trailer component. The precise maintenance routine depends on the manufacturer.

In all cases, a harder ride is a sign that the suspension needs your attention.

Check brakes

Brakes are one of the more important parts of a trailer, yet they also require the most maintenance. Not only are they constantly subjected to high stress when in use but they are also routinely immersed in salt water.

The degree of maintenance depends on the nature of your boat. For example, loads (i.e. an Aggregate Trailer Mass, also known as the ATM) under 750kg do not require an independent braking system, whereas an ATM exceeding 2000kg requires an independent power and breakaway unit.

Lubricate all components including the brake lock tab and hitch actuator. Check the discs and calipers for corrosion and wear. Thankfully, brake pads are cheap and easy to replace. Uneven patterns on the rotor strongly suggests the brake is not functioning as required. Also inspect the brake-cables or brake fluid. It is not unusual for cables to require occasional adjusting and remember that fluid does need replacing.

Test the lights and wiring

Electrical faults on a boat trailer can be troublesome because the root cause can be difficult to isolate.

Start by ensuring all lights work. A plug testing kit is a great way to isolate problems, as you can quickly determine whether the fault is limited to the trailer. Dirty connector plugs should be cleaned (use an electrical contact cleaner). Check the ground wire for corrosion or fraying, as it’s common source of problems.

If you have an older trailer, strongly consider upgrading the lights to LEDs (but don’t mix LEDs with incandescents). This is also a perfect time to thoroughly inspect all wiring, which again can be subject to corrosion.

Check the winch and straps

A broken winch strap is never fun, particularly if it snaps on the ramp during retrieval.

Lubricate the gears, and check the tie-downs, shackles and chain. Winch straps and tie-downs are notorious for degrading and eventually breaking as a result of prolonged sun exposure. Discolouration is a sign that the material has sustained some UV damage.

While you’re at it, pull out a decent length of cable or strap and check for fraying or other deterioration.

And finally

Secure your boat, regardless of whether it’s for winter or the weekend. Avoid storing easily stolen items like fishing gear, electronics and flares in the boat. Many anti-theft devices like trailer locks and wheel clamps are available, as are high-tech GPS and microdot options — but hopefully, by applying common sense, you won’t have to resort to using them in the first place.

And in case your boat trailer or tow vehicle break down on your way to and from the boat ramp it pays to have an emergency backup which is why RACV Marine offers Emergency Roadside Assistance for boat trailers and tow vehicles. While we genuinely hope you don’t get stranded, different packages are available to cover your style of boating in the event of an emergency. Call 13 11 11 and we’ll help get it sorted.

Most importantly, have fun on the water.

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