Trailer tires lead a tough life. Between heavy loads, hot pavement, and exposure to the elements, it’s no wonder trailer tires wear out more quickly than other tires. In fact, nearly half of all trailer tires on the road are dangerously worn out before they even reach 5 years old! As you can imagine, driving on worn-out trailer tires is risky business. Blowouts, reduced traction, and swaying trailers can lead to catastrophic accidents.
So how long should a set of trailer tires realistically last? And what can you do to maximize your trailer tires’ lifespan? I’ll cover all that and more in this informative guide on extending the life of your trailer tires. Read on to learn how proper tire care, maintenance, and selection can prevent blowouts and keep you rolling safely for years.
Monitor Tire Tread Depth
The most critical factor in determining trailer tire lifespan is tread depth. Trailer tires are legally considered worn out when tread depth reaches 2/32”. New trailer tires typically start with 10/32” or 12/32” of tread when installed. As the tire rolls down the road, the tread slowly wears away. Shallower tread provides less traction and grip, especially on wet roads, and causes trailer tires to hydroplane more easily.
Once tread depth reaches the minimum legal limit of 2/32”, it’s time to replace your trailer’s tires. But waiting that long is risky. Most experts recommend replacing trailer tires when tread depth nears 4/32”, before it wears down to the wear bar indicators molded into the tread grooves. An easy way to check tread depth at home is by using the penny test.
Simply insert a penny into the tire’s tread groove with Lincoln’s head upside down. If you can see the top of Lincoln’s head, your tires are at the minimum legal limit of 2/32” and it’s time to replace them. If you can’t quite see the top of his head, you likely have 3-4/32″ of tread remaining, but it’s still wise to start shopping for new trailer tires soon.
Tire Dry Rot – The Silent Killer
Even tires with plenty of tread remaining can fail due to dry rot. Prolonged exposure to sunlight, underinflation, improper storage, and extreme weathering causes the rubber compounds in a tire to break down. This leads to cracking on the tire’s surface and deterioration within the rubber.
Dry rot can strike trailer tires within just a few years if left uncovered and unprotected. Damaged from dry rot, trailer tires become unsafe to use even though their tread depth remains legal. Inspect tires regularly for cracks, crazing, and discoloration, which indicate the presence of dry rot. Keep tires covered with a tarp when not in use to block UV rays. Storing tires indoors and away from heat sources will extend their life.
Maintain Proper Tire Inflation
Underinflated trailer tires build up excessive heat as their overworked sidewalls continuously flex with each rotation. This rapid heat buildup accelerates tread wear and damage. Before each trip, always check your trailer tires’ air pressure with a gauge and inflate to the maximum pressure listed on the tire’s sidewall.
Tire pressure monitoring systems are an excellent investment to ensure your trailer tires stay properly inflated. The consequences of chronic underinflation are severe. A severely underinflated tire can overheat and suffer a blowout failure in just a few miles. Over-inflation also reduces a tire’s grip and contact patch, so stick within 5 psi of the maximum pressure recommendation. Proper inflation is one of the best ways to extend trailer tire lifespan.
Choosing the Right Load Range
All trailer tires have a Load Range printed on the sidewall, which indicates the maximum load the tire is designed to carry at a certain pressure. For example, a Load Range D tire can support up to 3,640 lbs when inflated to its max pressure. Exceeding the load rating causes rapid wear and dangerous overloading. Know your fully loaded trailer’s total weight and distribute the weight evenly across multiple axles.
Upgrading to a tire with a higher Load Range increases your trailer tires’ weight capacity, preventing overloading damage. Just remember to never exceed the recommended pressures printed on each tire. Consult with a tire specialist if you need guidance choosing the right Load Range for your trailer tires based on your typical cargo.
Passenger, LT, and ST Tires: What’s the Difference?
When selecting new trailer tires, understanding the key differences between tire types is critically important. Passenger tires like those found on cars and pickup trucks lack the strength for towing heavy trailers. Light Truck (LT) tires are designed for heavy loads but still are not ideal for trailers.
Only use Special Trailer (ST) tires specifically engineered for trailer axles. ST tires have stronger sidewalls, better heat dissipation, and optimized tread designs to suit the demands of towing. Never use ST tires on tow vehicles – they are for trailers only. Match your new trailer tires to your axle size, load range, and speed rating for optimal safety and performance.
Regular Inspection Is Key
Like any tire, trailer tires have a finite lifespan and require diligent monitoring and care for maximum longevity. Completing the penny test, checking for cracking and proper inflation before each trip, and weighing your loaded trailer can identify issues before they cause a dangerous road failure. Consider scheduling an annual tire inspection by a qualified mechanic.
Staying on top of your trailer tires’ condition through careful inspection and attention will keep you, your cargo, and your tow vehicle safe on the road. Don’t let a blown tire ruin your trip. With proper tire selection, inflation, and care, you can rely on your trailer’s tires for many more miles down the road.