Why a relative replaced some perfectly good Michelin Tires?

The other factor is daily driving. After the wife wore her Michelins on the 2001 Cherokee almost bald, we put on a new set. I took the "bald" tires and put them on our back-up car (1992 Cherokee) which had tires with tread but they were over 10 years old.

The back-up car is only driven around town on errands once in awhile (in dry weather). I don't consider it a danger putting around at 25-35 mph. It seems I'm not alone, many Mexicans here run tires until there is no visible tread. Not the safest practice, but many get by doing it.

I find there is an overflow in Mexico of two types of businesses-pharmacies and tire shops. Seems to be one or the other on every street corner around here. The guys in the mom and pop tire shops sit around all day waiting for a customer. Not only will they not turn away a flat repair, they do it right with a patch on the inside for about $50 pesos (at current exchange rate that is $3.00 usd).