Complete Guide to Trailer Tires: The Right Specialty Trailer (ST) Tire for the Job

Original publication date: June 22, 2022

In this guide, Tire Agent covers:

• The meaning of ST tire

• Bias ply vs radial trailer tires

• List of trailer types

• How to read tire codes on trailer tires (speed and load ratings)

• FAQ&As about trailer tire costs, sellers, and maintenance 

Would you attempt to hammer a nail into a piece of wood with a screwdriver? While it may eventually work, you open the door to a host of unnecessary hazards and dangers ... think throbbing fingers or worse. Simply put, using the right tools for the intended job is all about safety, and the tires you use on your trailer are no different. Just as there are hammers for nails, specialty trailer (ST) tires are important tools for ... (yep you guessed it) trailers. Now that we're on a roll, let's keep up the momentum and explore the ins and outs of trailer tires.

What Is a Trailer Tire? Can ST Tires Hold Their Weight?

Trailer tires, also called specialty trailer (ST) tires, are engineered to make light work of heavier loads. These specialized tires are formulated to go the distance while carrying boats, campers, utility trailers, and just about any and everything you'd pull behind another vehicle. One of the defining features of trailer tires is their thicker sidewall structure, which serves multiple purposes.

Thicker sidewalls boast higher load-bearing capacity.

The unique construction of trailer tires delivers more durability, even in the face of the higher tire inflation pressure required by heavier loads.

Trailer tires are resistant to bruises.

The purposeful construction in stiff shoulders of trailer tires and rubber compounds help trailer tires achieve more resistance to bruises.

Trailer tires are engineered to reduce sway.

Most importantly, trailer tires are formulated to reduce sway as you travel down the road at higher speeds. This can help keep you and your cargo secure for longer hauls. Before you put the pedal to the metal, though, understand this: You should always follow posted speed limits, especially when you're towing a trailer.

Types of Replacement Trailer Tires: Bias Ply vs Radial STs

When it comes to choosing replacement trailer tires, there is an array of sizes, but all trailer tires will fall into one of two categories: bias play trailer tires vs radial tires. While both types of tires are designed for towing, each has unique benefits and performance capabilities.

Radial trailer tires

Radial tires are designed with robust steel belts that run at a 90-degree angle to the tire's center line. Most radial tires are designed for heavier loads and have extra reinforcement. A few key attributes of radial tires:

• Quieter, smoother ride

• Excellent puncture resistance

• Less rolling resistance, which can help fuel economy

• Tend to run smoother due to the steel mesh's ability to dissipate heat, which can add to the life of the tire and reduce the likelihood of a blowout

• Improved sway control

• Wider footprint that can add to the life of the tire

Bias ply trailer tires

Bias play tires are engineered with nylon belts that run at a 30 to 45-degree angle to the tire's center line. A few key attributes of bias-ply tires:

• Designed to support heavy loads

• Typically cost less than radial tires

• May offer reduced performance when driving on curves, but do well when driving straight because the pressure of the load may cause the shape of the tire to change when driving

• Heat and abrasion may negatively impact the tire due to the shape change

Which type of trailer tire should I choose?

In terms of choosing the best trailer tire, best fifth wheel tire, best camper tire, etc., it's all about what's most important to you as the driver. Our advice: Go with whatever your trailer manufacturer specifies. Never "downsize" trailer tires. In other words, whatever size, speed rating and load index is indicated on your trailer, don't try to save money by purchasing smaller or lower rated tires. And, never buy used tires for any type of vehicle.

If you are considering all terrain trailer tires or mud terrain trailer tires, these do offer more protection against punctures than trailer tires that have been designed for highway usage. A/T and M/T trailer tires are indicated for people who haul fifth wheels and tow-behind RVs over rugged terrains. They might also be used for horse trailers and other types of trailers that are driven on rugged surfaces.

What Vehicles Require Trailer Tires?

Because of the unique, purposeful design of trailer tires, it's imperative to use an ST tire if your vehicle requires it. How do you know if you need trailer tires? These types of vehicles use trailer tires:

• Boat trailers

• Campers

• Toy haulers

• Fifth-wheel trailers

• Travel trailers (bumper-pull and pop-up campers)

• ATV trailer

• Utility trailers for lawnmowers or landscape equipment

• Cargo trailers

• Livestock trailers

• Pull-behind trailers

• Horse trailers

• Small utility trailers (flatbeds, haulers, or enclosed trailers)

• Heavy-duty trailers

• Motorhome

Here's one good rule of thumb: Special trailer (ST) tires are only intended for trailers. These tires are not suitable for wheels that steer or drive. You cannot use trailer tires on a truck, and you should not use truck tires on a trailer, for example.

Understanding Specialty Trailer Tire Ratings & Criteria

Because ST tires are used in such an array of applications, the load-carrying abilities will vary based on the performance handling requirements for each application. Let's look at some of the most important specialty tire rating characteristics.

How do I find the trailer tire size?

When choosing tires for your trailer, you should always refer to the type, size, and load range listed in the trailer's owner's manual or certification label. Look for the safety placard, which will be in different locations depending on the vehicle. RV owners look inside the glove box, on the door panel, or on the hitch. Fifth wheel and travel trailer owners, look on the left driver's side corner of the trailer itself.

Trailer load range

Special trailer tires will all have what is called a "load range," which represents the hauling capacity of the tire. The load range will always be located on the tire's sidewall and will be rated with a single letter, such as B, C, D, and so on.

Trailer tire load range chart

Source: Felling.com

ST (specialty tires) will have load ranges between C (6-ply) and H (16-ply). As you would assume, the higher the letter and number of plies, the heavier loads the tires can withstand. While the tire may have a higher load range, it will not increase the capacity of the actual trailer.

Trailer speed rating

The majority of trailer tires will have a maximum speed rating of around 65 MPH. The speed rating of a trailer tire is based on laboratory tests and has been established to match the speed capability of the tires. While there are trailer tires with higher speed ratings, most are designed to be safely operated at 65 MPH. Exceeding this speed can cause the tire to heat up faster and fail easier.

This is important: Just because you see a trailer tire with a speed rating of M doesn't mean you can fly at 81 mph! It means that the M-rated trailer tire is engineered to last longer, and it is more durable.

Trailer Tire Frequently Asked Questions

If you have trailer tire questions, Tire Agent has answers. As experts, we have provided answers to some of the most frequently asked questions about trailer tires.

How much do trailer tires cost?

Like most products, the price of trailer tires can range based on the tire size, type, quality, and brand. However, most trailer tires will range between $70 and $150. When you buy trailer tires online from Tire Agent, we include shipping to most addresses within the U.S. for free. Because we don't install tires (we are an online seller of tires and wheels), we don't charge for tire installation. We ship to any residential or commercial address, plus we offer a number of easy payment plans. If price is a concern, these payment plans can spread your cost over several months, to help you defer a bit lump-sum expense.

How long are trailer tires good for?

When we talk about the longevity of trailer tires and RV tires, we have to take a couple of things into consideration that we wouldn’t normally consider with passenger tires. Because specialty tires aren’t typically used on a regular basis, you have to consider both mileage and age. Camper Report explains it this way: If you put 10,000 to 15,000 miles on your trailer tires every year, they’ll probably wear out in about 5 years. If you put less than 5,000 miles a year on your trailer tires, then they’ll last about 6 years. In a separate post, we explain the expected life of tires, which, in short, explains how the organic rubber compounds start to break down after about 6 years.  

Do trailer tires need to be balanced and rotated, like vehicle tires?

Great question! 

We’ve found credible sources that have said both yes and no. On the “yes” side, RV Blogger says rotating and balancing tires helps with ride comfort, tire longevity and safety. On the flip side, Etrailer.com says you can rotate your trailer tires if you want, but you don’t have to because the utility of a trailer tire is load support, not smooth rides.

What's the difference between car tires, truck tires, and trailer tires?

Car tires, truck tires, and passenger vehicle tires are all designed to move people with comfort and safety in mind.

Trailer tires, on the other hand, are engineered specifically for towing. The material that makes up the sidewall of trailer tires is much thicker than the material on passenger tires. Because trailer tires aren't tasked with handling sharp turns, the tread is primarily focused toward the middle of the tire to help manage heavy loads. These heavy-duty load capacity tires boast up to 40% more load capacity than passenger car tires (P) and 10% more load capacity than equivalent light truck (LT) tires. ST tires also have shallower treads to help them wiggle less and improve your two vehicle's fuel economy.

Can you put trailer tires on a car?

No! You should never put trailer tires on a passenger vehicle. As we mentioned, trailer tires have entirely different structure and are engineered to respond differently to stressors. Placing a trailer tire on a car could negate your ability to brake, turn, and accelerate. This could create an unnecessarily dangerous and potentially disastrous situation.

Can you put car tires on a trailer?

No! You should never use passenger tires on a trailer. Passenger or car tires are typically loaded at a load range B, which is a 4-ply equivalent. This rating can be attributed to the fact that the sidewalls on a passenger tire are designed to be flexible to deliver a smoother ride. While this works excellently for a car, it's far too flexible for trailer use. Passenger tires are not engineered to stabilize heavier loads or manage the higher temperatures associated with normal use.

What's the best place to buy trailer tires?

Locally, you’ll find trailer tires at local stores that sell utility trailers, boat trailers, and RVs. For the largest selection of trailer tires and for ease of shopping from the convenience of your home or on the road, shop online with Tire Agent. We offer free and amazingly fast shipping within the U.S. for all in-stock tires. We can ship to your tire installer (we’ll include your details on the invoice) or to your home or place of business. If you’re looking for cheap trailer tires for sale, filter by price. The best way to search Tire Agent for your trailer tires is from any page, select Shop >> Shop by Size. Confirm fitment and size, and then browse by price, brand and other features. 

And what are some of the best trailer tire brands?

The following is a list of some of the best-selling trailer tires for utility trailers, boat trailers, towable trailers, RVs and campers. 

• Atturo ST 200 (starting around $120 per tire*, available in 13”, 14”, 15” and 16”)

• Carlisle Radial Trail HD (starting around $109 per tire, available in 13”, 14”, 15” and 16”) 

• Carlisle Sport Trail LH (starting around $115 per tire, available in 12”, 13”, 14”, 15” and 16”)

• Carlisle CSL16 (starting around $218 per tire, available in 15” and 16”)

• Goodyear Endurance ST (starting around $162 per tire, available in 14”, 15” and 16”)

• Hankook Vantra Trailer ST01 (starting around $161 per tire, available in 13”, 14”, 15” and 16”)

• Hercules H-901 ST (starting around $201 per tire, available in 15” and 16”)

• Lionhart LH-STR (starting around $129 per tire, available in 14”, 15” and 16”)

• Supermax STM-1 (starting around $96 per tire, available in 13”, 14”, 15” and 16”)

• TBC Trailer King RST (starting around $86 per tire, available in 13”, 14”, 15” and 16”)

*Prices subject to change. Check our Deals page for the latest rebates, coupons and instant saving offers.

We’re happy to help!

Need help choosing the right tires for your motorhome, toy hauler, boat trailer, camper/camping trailer, or travel trailer? Our team of highly trained experts has the knowledge and passion to help. You can reach us by phone, chat or email. We're always here to help!

Main Photo Joshua Rainey | Dreamstime.com