Tyre damage - what's the cause?

My wife has had her 2009 Ford Fiesta Zetec 1.2 from new and it has done 21000 miles.

On checking its tyres today I have just noticed that three of them (all Hankook Ventus S1 Evo 195 – 50 R15 fitted from new) have what appears to be fine cracks in the outermost “troughs” of each tyre, running circumferentially. The fourth tyre, a Dunlop, was new from January 2012 and has no cracks. All the tyres have at least 4mm of tread on them

I’ve not seen this before; should this happen to tyres after this time and what should I do?

Asked on 7 March 2014 by Alan49

Answered by Honest John
Quite common. Tyre life is only 5 years when subject to UV rays. Seek an opinion from someone who does not have an interest in selling you a new set of tyres.
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