Our tyres were 4 years old and a whole area of tread measuring about 4"x3" had come away, just after a long trip to France, and we use our caravan a lot, surely that was down to the level of use?
No that was a tyre failure not wear & tear. It could have happened for a number of reasons but not simply mileage. Tyres normally run for 20-30k miles or more before the tread is worn to legal limit but the casing should not fail as with yours, it does suggest tho that the 5 yr change cycle is good advice.
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