Guest Author - Evanne Schmarder

Do you remember that iconic tire commercial that extolled the virtues of their product – “because you’ve got a lot riding on your tires” – with an image of the cutest baby sitting in a tire? It was true then and it's true now – your tires are literally where the rubber meets the road. Making a good purchasing decision and maintaining your RV’s tires can mean the difference between a pleasant trip and an unpleasant, unplanned stop. In this article we’ll discuss the specifics of trailer tires but several points pertain to motorhomes as well.

Purchasing Trailer Tires

Look for special trailer tires – denoted with an ST in front of the string of numbers on the sidewall. These are designed with trailering in mind – they have stiffer sidewalls than a P (passenger) or LT (light truck) tire, are more flexible cornering and backing, and are designed for long duty cycles to name a few differentiating factors.

When choosing trailer tires you’ll need to know the weight of your fully-loaded trailer. It’s a great idea to actually weigh it – the manufacturer’s numbers are almost always low. This information is critical in determining the load range (weight capacity of each tire) you’ll need. Trailer tire load ranges are identified by a letter – usually B-D – the higher the letter the more the tire can carry. Remember that your tires work in conjunction with the axles and other suspension components – a high load range tire doesn’t mean you can exceed the axle ratings, etc.

Believe it or not, trailer tires are designed to last 3-5 years or 5,000-12,000 miles and are not designed to wear out. After a mere 3 years – traveling or garaged – approximately one-third of your tire’s strength is gone. Without question, it’s extremely difficult to purchase new tires when yours look perfectly good but it’s essential to your safety. Using sidewall data you can see how “fresh” your tires are. Look for a four digit number following the DOT serial number – typically on the back of the tire. The date code will be stamped rather than molded in an oval shape. The first two digits are the week of the year in which the tire was manufactured (01 thru 52) followed by the final two digits denoting the year it was manufactured. A tire stamped "1206" was manufactured in the 12th week of 2006.

Safe Travels

The number one factor in tire failure is improper inflation. It’s recommended to inflate your tires to the maximum PSI stamped on the sidewall. The trick however, is to be aware of how the elements affect tire pressure. Higher elevations increase tire pressure as does warmer temperatures. When traveling you should check your tires prior to setting out on the trip and each day before hitting the road – always when they are “cold” and that means before moving the vehicle. Take this opportunity to do a visual inspection, keeping an eye out for unusual tire wear, bulging, cracking, etc.

Another interesting and important fact is that ST tires have a maximum speed rating of 65 MPH. Drive faster than that and risk tire failure. That’s because as heat builds up the tire's structure starts to disintegrate and weaken. The load carrying capacity gradually decreases as the heat and stresses generated by higher speed increases. Plan enough time to get there without a tire mishap.

Bring and use tire covers for stays longer than a weekend – UV rays accelerate tire disintegration. Use only soap and water to clean your tires. Never – and I mean never – use a product with petroleum distillates on your tires. Again, this will degrade your tires.

Before leaving on your trip check your spare (when checking your other tires) and properly inflate it. Make sure you have all the pieces of your jack system and know how to use it.

Precious Cargo

Do yourself and those you share the road with a favor – make your tires your number one priority. Be slow, be prepared, be safe. The simple fact is that each one of us does have a lot riding on our tires. See you on the road…hopefully not on the side of the road.