Tire replacementby Tom Jones
If your RV tires are 5-7 years old it's time to replace them even if the tread looks good. RV tires typically have far less miles on them than car tires, but they also tend to sit for much longer periods. Exposure to sunlight, ozone, and ultra-violet radiation causes gradual loss of the plasticizers that keep the tires flexible and this can be exacerbated by lack of use.
Sometimes you'll see early signs in the form of cracks in the sidewall, but don't take the lack of visible cracks as any indication that the tire has a longer life. The author has seen first hand the sidewall of over-age RV tires fall apart as an RV was in motion. I was an observer and had just warned the driver that the tires weren't safe to be driven on, although they had accumulated less than 27,000 miles. Fortunately, the RV was moving very slowly and nobody was hurt. But, if this had been at highway speeds, the result could have been much different.
How do you tell the age of your tires if you weren't the original owner? The following explanation was excerpted from the RV Glossary Of Terms compiled by RV Forum staff member Don Jordan:
The National Highway Traffic Safety Administration (NHTSA) Tire Identification and Record Keeping Regulation, revised July 2, 2000 specifies a new 4-digit date code that must appear on all tires sold in the United States. The complete DOT (Department of Transportation) code is in the following format: DOT MMM SS TTT DDDD where MMM is a 3 digit manufacturer ID; SS is a tire size 2 digit code; TTT is an optional tire type code; and DDDD is the date of manufacture code where the first 2 digits indicate the week of manufacture and the second two digits are the year, i.e.: 2802 would indicate that the tire was manufactured the 28th week of 2002.
Note: tires manufactured before July 2, 2000 had a 3 digit date code where the first 2 digits are the week of manufacture and the last digit is the year. Tires manufactured in the 1990’s had a triangle following the 3 digit code while tires manufactured in the 1980’s did not, i.e.: 282 with a triangle would indicate that the tire was manufactured the 28th week of 1992 while if there is not a triangle following the 3 digits it was manufactured in the 28th week of 1982. The newer 4-digit code eliminates any ambiguity in the year of manufacture and allows continuation of the system through the 21st century.