As unlikely as it may seem, the steel leaf springs used with trailer and caravan suspensions are not immune to breakage. Overloading, metal fatigue and corrosion are among the most common causes of spring breakage, and the consequences can be catastrophic.
Regular inspections are the best way to guarantee their serviceability. That means it’s important for trailer owners to know the signs of imminent spring failure before it happens. And it’s also to good know that there’s a reputable source of replacement spring parts on the Australian market that isn’t burdened by product availability or long lead times.
Recognising the Causes Of Leaf Spring Failure
Let’s be honest: whether it’s while jockeying onto a boat ramp, navigating through a cramped RV park, or on a track in the middle of nowhere, if there’s any chance of a trailer spring breaking, it’s going to happen at the worst possible time. A proactive inspection routine is crucial for owners looking to minimise these risks though, along with having a reliable source of heavy duty trailer springs and suspension accessories for their trailer’s make and model.
With so much emphasis typically on trailer lighting, tyres and even tow mirror setups, it’s easy to take suspension maintenance for granted. Under normal driving conditions, trailer and caravan springs aren’t supposed to break but they can, and the causes are more common than most trailer owners would imagine. This includes:
- Repeated, and severe overloading. The first rule of trailer ownership is probably the one that’s ignored the most: overloading. Not only does exceeding a trailer’s allowable Gross Trailer Mass (GTM) create hitchbar and handling problems, it can also lead to snapped leaves, sheared pins, and the possibility of slipper-type leaves slipping completely out of their brackets.
- Corrosion and fatigue. Whether it’s the result of not cleaning the springs after long muddy off-road trips, or prolonged exposure to salt-saturated coastal air, rust and corrosion can reduce hangars, plates and fasteners to scrap metal in no time. This is especially if a trailer is stationary for long periods of time, allowing rusted, unsprung weight to further lead to metal fatigue.
- Rough roads and hard driving. It’s impossible to dismiss owners’ driving habits as a very real contributor to leaf spring breakage. That’s because in addition to the problems caused by overloading and fatigue, the jarring and harsh impacts from poorly sealed and unsealed surfaces can cause fasteners to loosen or shear off, shackles to shift, or eyelets to crack where they’re bolted to the chassis.
With their high-strength, hot-formed carbon- and spring-steel compositions, leaf spring packs are capable of delivering a lifetime of reliable service under ordinary driving conditions. That’s precisely why it’s so important for drivers to be able to recognise failure indicators before they happen. Fortunately, the simplicity of trailer and caravan spring design makes diagnosing problems quick and easy, while also keeping the cost of remedying them significantly lower.
Understanding Why Leaf Spring Inspections Are So Important
If the thought of an axle under a fully loaded trailer suddenly sliding out of its fixed position at 100km/h sounds terrifying, it is. This is exactly what can happen though if a trailer spring mishap occurs on the road. That’s why setting out a schedule for periodically inspecting camper trailer springs before they fail is so important.
Again, the simple packing of leaf springs makes carrying out thorough visual inspections an effortless process, one that should include:
- Locating obvious cracks, bends or breaks. Owners want to locate obvious physical damages like cracked, bent or broken leaves and frame hangers as quickly as possible. These are critical suspension elements and points that may have already failed but wouldn’t be visible unless specifically searched for, and require immediate replacement before putting the trailer back on the road.
- Verifying spring arc, and leaf and wheel alignment. If the spring leaves aren’t correctly aligned or aren’t arced in an upward direction, there’s an excellent chance that they’re experiencing metal fatigue and are on their way to failing. Likewise, if the trailer body is leaning more to one side than the other or the tyres aren’t evenly aligned with the body, these are clear signs of spring damage that need to be addressed as soon as possible.
- Checking for warped or missing hardware. Warped, stretched or missing hardware like shackles, bushings and fasteners might have already revealed themselves in the form of excess trailer sway or wobble. The visual signs, however, would include excess space between the leaves, or signs of repeated metal-on-metal strikes, both of which need to be alleviated before taking the trailer on the highway.
Although the sudden snapping and scraping sounds that would following a leaf spring failure while driving are unmistakeable, there’s no avoiding the fact that spring failures rarely ever occur spontaneously. A trailer that’s sagging to one side, or is giving off audible clunking or banging noises if pushed against when parked is likely encountering a spring problem. A careful inspection can reveal the source of the problem; and once it’s identified, owners need to be sure that they have a reliable source of trailer springs for sale that they can count on for maximum support.
Replacement Leaf Spring Parts That Owners Should Always Have Onboard
Make no mistake: it’s understandable why trailer owners would want to be able to identify which parts or assemblies need replacing before heading out on the road. Unfortunately though, that can’t always be the case, which is why it makes sense for them to always have a few critical repair and replacement parts onboard. This is where the value of getting to know a high quality parts retailer can pay a powerful dividend.
From the heaviest duty shackles and leaves, to the tiniest bushes and bolts, when it comes to expertise in trailer and caravan springs, Australia trusts vendors like NSW’s TTP for all their suspension needs. With a supplier roster that includes the likes of AL-KO, Cruisemaster and Fineline, they stock one of the largest replacement suspension and spring for trailer selections in the country, making them the perfect source for crucial parts that every trailer owner should always have on hand, such as:
- Shackle links. Shackle links connect the spring eyes to the hanger, and are prone to breakage due to their constant motion, especially on uneven terrain.
- Spring eye bushings. These bushings are made from either nylon or bronze, and are subject to cracking as a result of the heavy friction.
- Nylon nuts. Because steel nuts may be impossible to remove if rusted, nylon nuts are an excellent replacement for securing shackles and U-bolts.
- U-bolts. U-bolts are prone to bending or stripping under hard riding, and may need to be replaced in order to hold the spring from slipping.
- Tie plates. Tie plates secure the spring to the axle, and may need to be replaced if the become bent or their bolt holes become elongated.
And for trailer owners who have sufficient space and aren’t troubled by the extra weight, it makes sense to consider strapping a complete extra spring pack to their trailer frame. It’s the best assurance against having to potentially leave a trailer unattended for days until a replacement spring pack is obtained.
The Final Word
At the end of the day, it’s important to remember that regardless of whether a leaf spring fails on the road, or if a defect is detected only minutes before hitting the road, safety is still paramount. By nature, most spring faults are severe enough that unless it involves moving the trailer off of an active roadway, continuing to tow it would be illegal. That’s why frequent suspension inspections are so essential.
Breakage can still happen though, which is why heavy duty repair and replacement trailer springs and spring accessories are the keys to keeping trailers on the road. And with a reliable retailer to acquire them from, trailer owners never have to worry about having to leave their trailer on the side of the road.
