How do you know that you need a new boat trailer?

A quick visit to any boat ramp will tell the story of those who look after their boat’s ride, and those who don’t. 

Most of the times, it’s not your fault, either; you’ve bought a boat sitting on a trailer where the previous owner has left things a little too alone, creating problems that will severely limit the serviceable life of it.

A new trailer can be a big lift to your boating experience, looking after the boat and giving you peace of mind to travel further and visit new waters.

What are these signs? Let’s go through some of the common causes for concern when it comes to rating the life left in your trailer.

Galvanised steel trailers need a lot of attention if they are regularly immersed in saltwater.

A common and cheap method of making trailers was to use box steel, which was then dipped in a zinc-based galvanising bath to protect the steel against surface rust.

To keep it light, trailers were usually made of 3.0mm thick sections welded together. The important bit is it is only 3.0mm thick.

That means if rust is flaking off the trailer, that box section it flaked from is no longer 3.0mm thick. In other words, it has lost strength.

One of the problems with trailers made from box section is that while it’s easy to see rust on the outside, you couldn’t really see what was happening on the inside where the slow rot could be worse.

You can tell how much rust a trailer has in it by the amount of flex the trailer has as you tow it. A boat that’s always moving around on the trailer is a sure sign that the trailer’s structural integrity is not as good as it should be.

Modern trailers are built quite differently to the old box steel frame days. Changing the way trailers are made, such as using aluminium instead of steel and C-channel and I-beam frames that shed water rather than holding it, and are easier to clean.

An important place to check for rust is the wheel hubs. Water inside the hub can create all sorts of problems from reducing the effectiveness of the grease used to lubricate the bearings to rust creating pitting on surfaces that should be smooth.

It’s surprisingly common to see older boat trailers with either missing, chewed-out or collapsed rollers and bunks – the plastic slides that support a boat’s hull – that have worn down to their rivets.

An aluminium hull can be much harder on rollers than a fibreglass hull. Nicks and chips on the keel of an alloy boat can work like the serrated edge of a knife, cutting into the roller as the keel slides along the trailer.

The most common cause of roller failure on older trailers are the split pins used to hold them onto their bracket.

The roller usually has a pin going through the centre of it that is clipped onto the trailer’s roller bracket either using a split pin fitted to one or both ends of the pin. If they are not stainless steel they can rust and fail, allowing the pin to slide to one side and drop the roller to the ground.

Likewise, trailers made using steel plate roller brackets can fail over time, and usually while loading a boat where the pressure placed on the rollers is much higher.

Depending on how old your trailer is, spare parts such as replacement roller brackets may be very difficult to find.

The bunks use galvanised steel box sections similar to your trailer, so any surface rust is a sign that the bunk’s insides are slowly rotting out as well.

While your boat may now have two batteries, an electric trolling motor and two fuel tote tanks can pulled by a modern, fast car, the trailer may have been built and rated to a lightweight boat with one battery and a single tote tank and pulled using a small, gutless family car.

As you add more gear to a boat, and pull it around much more time-efficiently – that’s essentially at a higher speed – behind your new trade ute, the stresses you place on an older trailer are amplified.

Again, it’s a case of looking at how your boat rides on the trailer as you drive along the road. If the boat is moving around it’s a sure sign the trailer doesn’t have the structural integrity to cope with a heavy boat and high speeds.

The other big benefit of a newer trailer over an older one is the ability to tune the trailer to suit your boat. You can easily add or remove rollers, use a heavier-duty winch, add a ladder to climb aboard the boat to drive it off the trailer and more.

Then there are the convenience things, such as easy-to-replace LED lights, modern mechanical and electronic braking systems and a swing-away jockey wheel that make the whole ownership experience so much easier.

The number of people driving a boat onto a trailer that wasn’t made for it is surprisingly high.

Driving a boat onto an older trailer is fraught with danger. For starters, the back of the trailer won’t be made for a boat to charge up it, missing out on the channels that drive-on trailers use to centre the boat as it rides up the rollers.

Miss even slightly while aiming at an older trailer and you’ll risk hull damage.

Regular trailer maintenance is the best way to keep you, your boat, and other people safe out on the road and at the boat ramp.

Rising maintenance costs are a strong indication it may be time to move on and buy a new trailer. If it’s common consumables, such as needing to replace the wheel bearings each year, the cost can add up over time, as well as becoming something of a landmine over time if you ever forget a regular check-up.