The "age" old question. Tires, installed new at Les Schwab in November of 2018, DOT date July 2016. Very small cracking visible in tread grooves and some also on sidewalls near rim. LT265/70R17 C Back Country, on 2005 GMC Sierra 1500. Still decent tread, truck primarily used around town, occasionally tow travel trailer in summer. Replacement time? Or since i don't put many miles on it, a couple more years of life?