Recently witnessing a nasty accident on the motorway in Gran Canaria, where fortunately all the passengers survived unscathed, made me ask some questions about the cause. Apparently, one tire had exploded, which was due to the age of the tire and failure of the rubber.

For me, this was an unknown phenomenon. Although I am careful about regularly checking the depth of tire tread from time to time, and changing a tire when necessary, I frankly had no idea that tires ‘age’ and that rubber deteriorates. Judging from conversations with other expats, most did not know this either.

We have a second vehicle, which is not heavily used and, since we live on an island, has very low mileage, because there are few long distances that can be traveled. The vehicle is parked on the road outside our home, and I have to admit that, for much of the day, it is parked in the full glare of the sun. The tires all look as good as new, but I took the car to the tire depot for a check – just in case.

Jorge, the mechanic, looked horrified when he pointed out that the tires were made in 2005, as a coding that represents the date is clearly inscribed on the tires. With, not undisguised delight, Jorge went on to point out some deterioration of the rubber, as well as unevenness on the walls of the tires. He made that inward sucking of breath that people make when they are about to impart bad news. I prepared myself. They were not exactly bulges, Jorge explained, but they were heading that way. Jorge then went on to show me a tire that had exploded, and inferred that the same would happen to me unless I bought a new set of tires. The exploded tire was not a pleasant sight, but it did help me to understand the problem.

Apparently, the performance of tires deteriorates with age, because they contain anti-oxidizing chemicals to slow the rate of ageing, but they need to be in use to be effective. My low mileage vehicle was deteriorating on the roadside, and because of the intensity of the sun and heat, the ageing process was accelerated, making the tires unroadworthy. Low mileage, older cars tend to be at most risk from premature ageing, explained Jorge, continuing with a sharp intake of breath and shaking his head.

Of course, the age of a tire and when it should be replaced depends upon many factors, but Jorge reckons that 6 years is about the age limit in a hot country. Living on an island, we also have a particular problem in that tires rarely reach the end of their life based upon the depth of tread alone. Distances tend to be short and expats, retired or otherwise, do not travel very far in a year.

Jorge pointed out that the date that tires are made is clearly inscribed on the wall of the tire, in the form of four numbers. These numbers indicate the year and week number that it was made; for example 2612 will be week 26 of 2012. This information can also be used to ensure that you are buying tires with the longest shelf life possible.

Jorge had successfully made his point and I reluctantly agreed to buy four new tires. I handed over my credit card, but I am now pleased that I did so since tires are the only contact that there is between the driver and the perils of the motorway. I think it was a good investment.