They do deteriorate with age, particularly if exposed to sunshine.

There was once moves to make them 'age limited' at MOT time, but it was quietly dropped. You can check the age of any tyre from the DOT code: www.carbibles.com/tyre_bible.html#top . Scroll down to 'DOT codes and the 6-year shelf life'.

All you need to do is check for excessive cracking. The level of grip will deteriorate with age, but not so much as many people would notice - when did you last squeal your tyres by cornering hard.

I wouldn't change mine unless there was any sign of deterioration.

Used to tow a caravan. In winter , removed wheels and stored dry, mounted on wall.

AFter 8 years, we had two burst tyres: both the 8 year old tyres - due to age fatigue.

After 8 years, rubber oxidises and fabric and steel stretch. I would replace them as a matter of personal safety and as routine maintenance. Of course, if you believe tyres will last forever, you may also wish to believe in lttle green men as well::-)

( We kept a 106 for 17 years and repalced tyres after 6 and 12 years despite 4-5mm of tread as personal safety - and safety of others - ruled over short term costs...)

I am sorry to see that people seem to know more about tyre degradation with age than the makers. Perhaps they can explain how tyres can last for so long and not deteriorate?

Most of the advice above is my my view misguided at best and irresponsible at worst... A high speed stop at 70mph on a really hot day after 50 miles of a motorway may very likely give you a lesson in age related fatigue...

Edited by madf on 23/06/2011 at 17:06