Sumitomo of (just an example, although specific) warrants the tires in question for 45K miles or 60 months (from DOM), whichever comes first. In this case, even the single 245/40R17 tire manufactured during the second week of January (0225, last 4 of DOT code) is >6 months old; no real issues and I decided to keep this one. The rest of the tires have date codes of 2823, 4523 and 1923 and I decided to get them replaced.
Car manufacturers such as BMW recommend discontinuing usage of tires irrespective of remaining tread life after 6 years.
s 18 and 23 for two respectively; I do not re,member the DOM for the
Separately, there are varying opinions on the WWW about such issues including sensationalized (to a bit) recommendations and responses. Of course, folks are free to make their own decisions

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