Where the Rubber Meets the Road – RV Tires
By: Ron Francoeur
There are many aspects of RV safety and one of the most important has to do with RV Tires. Your RV tires are asked to bear the weight of your RV and its contents at highway speed over less than perfect road surfaces and extreme weather and temperature variations and to do it all safely. A tire failure while driving presents a seriously dangerous condition that can cause considerable damage to the RV and/or injury to the people in it or in the surrounding area.
It behooves us as RV owners not to neglect our tires and to assure that they are in top condition before heading out on the road.
It all begins with having the correct tires installed on the RV. The last several RV inspections we performed all had Life/Safety issues with the tires. The most recent had new, name brand tires installed. They looked great – they were just the wrong tires for the towable RV. The RV data plate in the following photo calls for Load Range F tires. The new tires installed were load range E.
The load range specification by the RV manufacturer is determined for the anticipated load that the RV will place on each axle tire. Underrated tires will get hot and can suffer a blowout.
RV Tire Types:
Motorhomes typically use an LT tire (Light Truck) while towables will use an ST tire (Special Trailer).
Do not use ST tires on a motorhome. They are simply not designed for that purpose.
Some people have ‘upgraded’ their trailer tires from ST to LT class tires after experiencing trailer tire blowouts. It can be done, but with special consideration given to assure the LT tire can handle the load. A larger LT tire/wheel may be needed to match the load capacity, so check to make sure there is sufficient clearance on the trailer.
In truth, most ST trailer tire blowouts are largely due to inexpensive, inferior, imported tires as well as improper tire maintenance, excessive and imbalanced RV trailer loading, and travel speeds that exceed the tire speed rating. A name brand, quality ST tire can cost double the price of the import but is well worth it for safety and peace of mind.
RV Tire Age:
Unlike passenger car tires, your RV tires will most likely ‘age out’ before they wear out. Most often we will replace our RV tires between 5 to 7 years of age while there is significant tread remaining. You can determine your tire’s age by finding its birth date embossed on one side of the tire following the DOT code.
In this photo, the tire was born on the eighth week of 2016. Depending upon condition it would have been due for replacement in 2021 and no later than 2023.
RV Tire Condition:
In addition to the tire age, you should check the overall condition of the tire before each trip.
Look for sidewall deterioration such as cracks or checking in the rubber:
Look for sidewall damage from hitting curbs etc.:
Check the tread wear:
If any of these conditions are present, the tires should be replaced with quality tires that have recent DOT born dates.
Underinflated tires get hot and excessive heat leads to tire failure. The uneven wear pattern shown above was caused by underinflated tires. The tires can appear normal on the outside but the internal heat damage due to running underinflated can cause a sudden blowout failure.
It is recommended to weigh each tire/axle with a fully loaded RV. Then, using the tire manufacturer’s tire load/inflation chart for your tire, set your cold tire pressure accordingly.
If you don’t know the exact load on the tires, inflate them to the recommended cold pressure listed on your RV’s VIN data plate.
A good tire inflator is a must have tool in your RV. A compact, on-demand compressor like the VIAIR shown below is a popular item with RVers.
It is highly recommended that you have a Tire Pressure Monitoring System (TPMS) like the one shown below.
These devices keep you informed of the pressure and temperature of each tire and with preset limits will give you a warning should the pressure and/or temperature get out of the normal operating range.
Your RV VIN data plate specifies the maximum load that you can have on each axle. That is listed as the GAWR (Gross Axle Weight Rating). When you weigh your RV as described above pay attention that you are not exceeding the load specification for the axles and tires. Also note if there is an imbalance (too much weight on one side or the other) and adjust what you bring for cargo and where you place it accordingly.
Who doesn’t appreciate those shiny black tires after detailing your vehicle? The problem is that many of those tire shine products are doing your tires more harm than good.
Tires contain protectants that gradually work their way to surface while they are rolling. The use of harsh cleansers when washing the wheels and tires should be avoided as they remove the rubber protectant. Washing with a mild soap and water is sufficient. Some tire shine and so-called tire protectants contain petroleum distillates that are harmful and shorten the life of your tires.
A tire balm product like the 303-product shown above is water based and helps to provide protection to your tire rubber against UV rays.
Also, the use of tire covers is advisable when the RV is parked for an extended period.
If you are looking to buy an RV, be sure to hire a Nationally Certified NRVIA RV Inspector. You can find one near you at http://www.NRVIA.org
NRVIA Certified Inspectors subscribe to a strict code of ethics to assure you of the highest integrity and professionalism in the inspection work.
The RV tells its story, and the unbiased facts are provided to you in a comprehensively detailed and easy to understand report.
Having the knowledge of the true condition of the RV at the time of the inspection gives you the power to make an informed purchase decision.
Check out our web site for the inspection details and a sample report for review.
Sherlock RV Inspection Service, LLC
Office: 352 – 224 – 9477
Text: 678 – 360 - 6883