Going on a family road trip with a mini home is a dream of many people. You travel to a destination, enjoying a relaxed drive and spending time with your loved ones in nature, only to retreat to your recreational vehicle (RV) for a good night’s sleep. This experience is a tempting but costly investment. After all, you’re covering the cost of the vehicle, appliances, and tires, both during the purchase and the following maintenance.
Speaking of tires, the 225/70R19.5 size is commonly found on certain RVs and delivery trucks. However, there is one crucial difference in how the same tire size wears out between these two vehicle types. Delivery trucks, for the most part, wear out tire tread by covering many miles while transporting goods. In contrast, RVs are used for occasional road trips rather than constant driving. As such, RV tires are likely to age out before they wear out from use.
Regardless of the outcome, sooner or later, you’ll need a new set of tires for your vehicle. Before purchasing, it’s crucial to understand what kind of tires suit your needs. For this reason, it is beneficial to know what the symbols on the tire sidewalls are. So, let’s take a look at them.
Decoding the Sidewall: Beyond the Numbers
Getting familiar with the numbers and letters on the tire sidewall will help you find the appropriate tires for your RV. Whether you need the 225/70R19.5 size or some other size is irrelevant, as long as you understand what these symbols mean. Fortunately, deciphering them is easy because they list the tire’s details in the following order: tire width, sidewall height, construction, and rim diameter. As such, there’s no need to worry.
- 225: Represents the tire’s width in millimeters. Some tires have narrower or wider footprints, impacting their performance.
- 70: This is the aspect ratio, which is the relationship of the height of the tire’s sidewall to the tire’s width, expressed as a percentage.
- R: The R signifies a radial structure that supports the tire from within.
- 5: The last number is the rim diameter expressed in inches. It points out that the tire can be mounted on 19.5-inch wheels.
Besides these numbers and letters, you can also find additional information in the next sequence of numbers and letters. They are the load and speed ratings of a tire.
The load rating informs you how much load a tire can carry. It is shown through a numerical scale from 1 (102 lbs) to 150 (7385 lbs). However, some models can feature two load index numbers, such as 128/126. This means the tire in question has a 128 load index when used by itself, but if it’s installed on a dual-tire axle, it’ll have the 126 value.
The speed rating represents the maximum speed a tire can sustain for a long time, and, for the most part, it’s alphabetically ordered from A1 (3 mph) to ZR (over 150 mph). The exception to this rule is the H (130 mph) rated tires.
The “Silent Killer”: Tire Aging & DOT Codes
Whether you’re purchasing new tires or maintaining the ones you already have, it’s important to consider their age. Ignoring the age puts you at great risk while driving on them, because they can blow out at any point during your road trip. At best, this can only delay the trip, while at worst, it can have a more serious impact. So, let’s talk about the DOT code and how it can assist you.
The tire manufacturer’s date code, or DOT code, is located on the tire sidewall. It provides information about the factory and country where the tire was produced, while the last four digits indicate the date of manufacture. The first two digits represent the week, while the last two represent the year. If, for example, the last four digits of the DOT code are 1221, it means the tire was manufactured in the 12th week of 2021.
Knowing when your tires were produced allows you to estimate their general condition. The older your tires are, the more likely they are to deteriorate from the inside out. The age simply gets them through a process called dry rot, which occurs slowly over time. UV rays, extreme temperatures, corrosive chemicals, and ozone greatly contribute to tires drying out. These factors impact the rubber compound molecules, breaking them down and compromising the structural integrity of tires, which results in blowouts.
The danger of dry rot lies in the fact that it can greatly affect the tire without you noticing, particularly since the process starts from the inside. By the time cracks appear on the sidewall, you may need to replace your tires as they’re no longer flexible but brittle. Tires on RVs are particularly susceptible to dry rot. Their lack of use, and if the vehicle is parked outside, leaves them exposed to the outside factors like heat and UV rays for prolonged periods of time, which accelerates dry rot.
While the aging of tires and dry rot are current issues, the tire and vehicle technologies are rapidly changing, offering new benefits and safety improvements for drivers. These technologies may redefine driving in the future.
Maintenance for Longevity: Pressure & Protection
While tire aging and dry rot are factors to look out for, it doesn’t mean that you shouldn’t pay attention to other aspects of your tire maintenance. After all, tires do need regular checkups, both from you and your mechanic. So, let’s take a look at what you can do to extend the lifespan of your tires.
Regardless of your machine, all tires need to be inflated to the optimal pressure for them to function properly. Overinflating or underinflating your tires leads to uneven wear, significantly reducing their longevity and impacting fuel economy and road safety.
RV tires should be inflated to the value found on the manufacturer’s chart. Since RVs are not always perfectly balanced weight-wise at each tire position, you should measure the weight of your RV at these specific places to find out the appropriate pressure level for each tire. Wheel position weighing should be done every three to four years.
Another way to ensure the longevity of your RV tires is to protect them from harmful UV rays and ozone. Using protectant sprays on your tires can be beneficial. Make sure to do thorough research since some products can cause more harm than good. Protecting them against the sun and weather can be achieved with tire covers as well.
In addition, keep your tires clean, but don’t use aggressive chemicals. This can help you when performing visual checkups, allowing you to spot uneven tread or tread cracking. Noticing the latter is important as it is one of the signs of dry rot affecting your tires. Spotting this issue early on allows you to replace your tires and avoid a potential accident during your trip. Do not underestimate the importance of regular maintenance.
Pre-Trip Inspection Checklist
After making sure your vehicle and tires are in order, it’s time to inspect if you’ve prepared everything for your trip. It’s better to do a double check rather than regret not bringing an important item with you and ruining your vacation. In order to avoid this possibility, what necessities should you bring?
Having all documents with you is obligatory when crossing a border. You don’t want to cancel a trip just because you forgot them. Maps and navigation are also handy in order to keep track of where you are and which way to go to reach the desired destination. You don’t want your trip to be memorable for getting lost.
While you’ve ensured your machine is functional, you never know what can go awry during the trip. Keeping a tire pressure gauge and the rest of the basic toolkit can help you in case of an emergency. A screwdriver, wrench, and flashlight are simple but necessary items you might need to overcome a hurdle.
Aside from keeping the vehicle operational, you shouldn’t neglect your personal health or that of your companions. This means that no road trip should be undertaken without a first-aid kit and personal medication. Staying healthy also means having enough supplies in terms of water and food, and carrying weather-appropriate clothes.
Making a list of all essentials and keeping track of all items will allow you to enjoy a stress-free road trip with your family or friends. After all, it’s better to have fun with your group than cancel the event you’ve been looking forward to.
Conclusion
The conditions on the road can be unpredictable. Fortunately, you can control some aspects of the road trip. As your only contact with the driving surface, it’s crucial to invest in new 225/70R19.5 tires every few years, as this will minimize the risk of dry rot. Maintaining your tires will prolong their service life and ensure a safe journey. This is, of course, much better than having an accident along the way. In other words, you don’t need to be able to control everything, just enough to ensure a successful trip.
