3 Essential Tips for Trailer Leaf Spring Maintenance

A boat trailer’s leaf springs are its Achilles’ heel. In other words, most trailers are made of metal that doesn’t rust, but have a weak spot that does.   

Leaf springs are made from non-galvanized steel that, although incredibly strong and resilient, is highly susceptible to rust when it comes into contact with water. In other words, you’ve got a metal that rusts, that’s frequently exposed to water. This means you’re going to have to do some preventive maintenance on your trailer’s leaf springs if you want them to last. A well maintained set of trailer springs can last 15+ years. A neglected set, on the other hand, may need replacing after a few years.

Here are some maintenance tips to keep your trailer’s leaf springs corrosion-free and durable. 

Trailer Leaf Spring Maintenance Tip 1: Rinse Trailer After Use

The first step to maintaining a trailer — the whole trailer — is to wash it after every use.You don’t need to meticulously scrub the trailer, just hose it down with fresh water. 

Make sure you wash every part of it, including the leaf springs. Always inspect the leaf springs for any signs of damage when you’re rinsing them. Rinsing is especially important for trailers used in salt water, which is extremely corrosive. However, fresh water also contains corrosive salts and minerals, so it’s just as important that trailers used in freshwater environments also be thoroughly rinsed after every use to prevent corrosion. 

Trailer Leaf Spring Maintenance Tip 2: Apply a Water-Repellent Coating

Coating the leaf springs with a water repellent will prevent water from coming into contact with them, and increase their lifespan considerably. The common methods of water repellant coatings are spraying the leaf springs with a water-repelling lubricant and coating the leaf springs with a suitable type of grease after at least every 3-4 uses. 

Spray lubricants are easy to apply, but are not very durable, so the coating will need to be applied regularly. Grease coatings provide better protection against water, and are far less likely to wash off. However, applying the grease is a very messy process. If you decide to grease your trailer's leaf springs, use a marine grease that is saltwater- and heat-resistant, so it won’t melt and run off everywhere when left in direct sunlight.

Trailer Leaf Spring Maintenance Tip 3: Use Rust Inhibitors and Repaint 

Although a bit more labor intensive than applying water-repellent spray, coating the leaf springs with rust inhibitors will give them a new lease of life. Rust inhibitors should be applied to your trailer’s leaf springs to stave off corrosion. 

Before painting a trailer and its leaf springs, all oils and contaminants have to be removed with solvent (if you greased your springs this will be much harder), and any loose rust removed with a wire brush. To fully repaint leaf springs, they should be removed from the trailer, although you can repaint them while they’re still in place. How often leaf springs should be repainted varies depending upon frequency of use and exposure to water, but once every 2-3 years should suffice. 

Following these 3 maintenance tips should get you many years of use out of your leaf springs. However, remember that trailering components can still break despite your best efforts, and a cracked or broken trailer leaf spring will require total replacement.