Everything you need to know about RV Tire Care and Purchasing
In my opinion, the tires you drive on are just as important as the roof over your head. Making sure that your tires are well cared for will make traveling safer and save you money down the line from having to replace. The good news is, tire care is easy with the right knowledge and a few tools. In this blog, I am going to discuss RV tire care, signs of wear, and provide some tips when it comes to replacing the tires for your rig. Let’s dive in!
TIRE CARE
Did you know that the number one reason for tire blowouts is under inflated tires? Low air pressure in a tire causes the tire to flex more and lose its designed shape. This flexing causes excess heat generation which leads to a blowout. Another cause for blowouts is going over the tire weight limit. Excess weight causes the tire to break down prematurely and potentially damage the rigidity of the tire. It’s best to follow a tire load index chart if you are unsure if you are over, or near the limitation of your tire’s weight capacity.
Just as under inflated tires are dangerous, over inflated tires are equally as dangerous. Over inflating tires also causes the tire to change from its designed shape and creates a tire with less surface area to make contact with the road. The result? Poor handling and increased premature wear to the tire. It also means that braking will take longer and the tires are more susceptible to puncture or blowout. The good news is, just by simply keeping your tires inflated to the correct PSI (Pound-Force per Square Inch), you will drastically decrease the chances of a blowout.
Not sure what PSI your tire should be set at? Check the driver’s side door jamb to see if there is a sticker with the manufacturer PSI spec. If you are unable to find any sticker displaying this info, check your owner’s manual. Second owner, or lost the manual? Call the chassis manufacturer for this information.
Weather can also play a factor in the longevity of your tires, especially in the AZ summer heat. When the ambient temperature outside is over 100+ degrees Fahrenheit, the asphalt can get as hot as 170-180 degrees Fahrenheit in the afternoon sun. That is hot! To reduce the heat generation and friction of the tires on asphalt, make sure your tires are properly inflated and if possible try not to drive during the hottest part of the day.
Another common issue with RV tires is flat spotting. This issue occurs when a vehicle has been sitting in the same spot for too long. The tell-tale-sign is a rough ride that feels like you are driving on a bumpy surface but the road is smooth. Luckily in most cases, flat spotting will be temporary and the tires will correct their shape once driven as long as the tires have not been sitting for an excessive period of time and they were properly inflated.
Permanent damage is most likely to happen if the tires are improperly inflated, overloaded, the vehicle has been sitting for a month or more, or there are big swings in ambient temperature. To prevent flat spotting from happening, make sure the vehicle is moved or driven every couple of weeks for at least a mile to keep the tires in shape. If you are storing your RV, you can talk to your storage coordinator and request that your RV is moved every couple of weeks or monthly.
Harsh UV rays can cause premature wear and break down the synthetic chemicals in the tire leading to dry rot and cracks. If your vehicle is being stored outside and exposed to the elements, always make sure that your tires are not in direct sunlight or buy tire covers for your RV. Tire covers can be purchased from most RV dealers or retailers online.
Tire pressure monitoring systems (TPMS) are highly recommended for any RV/Trailer/5th wheel owner. These aftermarket kits have an LCD monitor display that sits inside your vehicle and indicates the tire pressure for each wheel. The kits come with transmitters that screw directly onto the valve stem. These systems run about $200-500 and are well worth the money to monitor air pressure as you are driving. Most of these systems can also be easily installed for any DIY readers out there.
SIGNS OF WEAR
The signs of wear for most tires are universal. In this section we will talk about the factors that lead to wear and how to notice when your tire has reached the end of its life.
The most important metric to discuss is age. Age can be tricky because your tires may look healthy on the outside and still have lots of tread. However, aging tires can lose structural integrity and be more prone to blowouts and damage. Most manufacturers recommend changing your RV tires every 3-6 years regardless of mileage, meaning even if you have only driven one thousand miles over 6 years, it is still recommended you replace the tires for safe transportation.
Not sure how old your tires are? Take a look at the sidewall of your tires and you will see “DOT” (Department of Transportation) followed by a 7-12 character code. The last four digits of this code indicate the week and year the tire was manufactured. For example, if the last four digits of the code read 2118, this would indicate that the tire was manufactured on the 21st week of 2018.
Another wear indicator is the tread depth on the tires. Tread depth is a vertical measurement from the top of the tire’s rubber to the lowest point of the groves in the tire. The tread is the surface that makes contact with the ground and wears down over time as the tire is driven. Tires with worn down tread are considered “bald” and can lead to a number of issues like decreased traction, poor handling, puncturing, blowouts, and slower stopping speeds. They are especially dangerous in wet and snowy conditions which can lead to hydroplaning and loss of vehicle control.
There are a few ways to determine tread depth, I prefer the more scientific methods. The first is by visually looking at the tires and investigating if the wear bars are visible. Wear bars are small tread marks on the tire that let you know when your tire has reached the lowest safe amount of tread. A second is to use a tire tread depth gauge. This tool will let you know how many 32nds of an inch are left on your tread. If you are unsure how to measure tread, I always recommend going to a tire shop or dealer and having a professional inspect your tires for tread depth. Checking tire tread is common practice at RV service centers.
Lastly, any damage to your tires can be dangerous. Bulging, cracks, or gouges can indicate that it’s time for new tires. For example, a tire that constantly needs air could need a new valve stem (air inlet), patch work, or be completely replaced. If you are constantly having to add air to one or more tires, it’s an indicator that there is a bigger issue. Bulging, cracked or flat spot tires are more likely to blow out due to change in designed shape.
REPLACING YOUR RV TIRES
When it does come time to replace your RV tires, the good news is, you have options. Just like there are many tire manufacturers for passenger cars, many of those manufacturers also make RV tires that will be a direct replacement for your factory tires. Before we go further, let’s discuss the different types of tires and how to read a tire code.
For towable vehicles, you will want to purchase Special Trailer tires or “ST tires”. These tires are different from passenger (P) and light truck (LT) tires because they have been designed specifically to handle higher weight capacities due to a thicker, stiffer sidewall construction and steel cords to provide better tensile strength. They also vary in size depending on the rim size and tire width.
The exact type of tire, including ratios of wheel height to tread and rim size are located on the tire. If you look on the sidewall of the tire you will see a reading that displays something like ST225/75R15. In this example, the ST stands for special tire, the 225 indicates width of tire in millimeters, the 75 indicates the ratio of height to width (aspect ratio), the R stands for radial (all modern tires are radial), and the 15 indicates the size of the rim. Whenever you are shopping for new tires, always make sure to get a replacement tire with the same type and size displayed on the sidewall of your tire. Getting an incorrect type/size tire can lead to multiple problems including rollovers and damage to the wheel well.
B vans, Class C, and larger Class A motorhomes also have varying rim sizes and require specific tires to handle the excess weight load of a motorhome. A similar tire code will be displayed on the sidewall of each of these tires.
When purchasing tires, I always recommend looking for a tire that fits within the upper end of your price range with a good warranty. Like with most purchases, you get what you pay for. Finding a good middle ground is key. I do not recommend opting for the cheapest tire available because these tires usually wear faster and can cost more in the long run to keep replacing. The “top-of-the-line” tires on the opposite spectrum are usually grossly overpriced for a tire that serves the same purpose and utility as the middle ground competition. Talk to a local tire shop and ask them recommendations for tires and shop price and warranty. Another way to save is to become a member of an RV Club. Some clubs, like Good Sam for example, have agreements with tire manufacturers that if you purchase through the club, you will get the tires at a discounted rate. Most importantly, do your research and make the decision that is right for you!
Tools to keep on hand:
Tire pressure gauge
Tire tread depth gauge
12v air compressor
Tire Pressure Monitoring System (Optional)