Spare tire needs attention, too
Q. Never miss your column in the Daily Herald. You have helped me with a gasoline octane question in the past. Thank you. My new question is in regard to the full-size spare tire in the trunk of my 2000 Jaguar S-Type.
When I have the four tires that were installed two years ago rotated and balanced, I never think about the tire in the trunk. Other than making sure it is inflated to the correct pressure, should I have it looked at for signs of deterioration?
I can't see where it would become a problem. It is in the dark and the car has been garage kept for the two years I have owned it and 12 years by the previous owner.
A. So it sounds like the spare tire is 14 years old? You can tell for sure by looking at the DOT number on the sidewall of the tire. Any tire manufactured after the year 2000 has a four-digit code — the final four digits at the end of the longer DOT number. The first two digits indicate the week the tire was manufactured and the last two will tell you the year.
If the tire is manufactured prior to 2000, they used a three-digit system; the first two digits are again the week and the last one is the year (without telling you the decade, so it's a little trickier).
The fact that the tire is not in the direct sun is good but think about the heat. The spare bakes during the summer tucked away in the microwave we call a trunk.
While there is no set amount of years we use as a guideline to condemn a spare tire, I think that one is old enough to warrant a replacement. While it probably would get you to a local repair shop in the event of a flat, I would not want to count on it if I had to travel a long distance.
If you have a spare mounted on the exact wheel as the four on your car, you can always keep the spare rotated in with the other tires. This will increase the life of all five tires. I hope this helps.
• Douglas Automotive is at 417 W. Main St., Barrington, (847) 381-0454, and 123 Virginia Road, Crystal Lake, (815) 356-0440. For information, visit douglasautomotive.com. Send questions to underthehood@dailyherald.com.