Hello,
I have a 2020 CRV, tire size is 235/60 R18. Hankook

They have 11K mi on them, left rear had a flat and tore the sidewall,
Look to get the exact same tire, new.

Some of the tire stores mention that there can't be more than 3mm difference between the
tire tread depth.....

How critical is this ?
Any thoughts experience ?

 

welcome to the forum. i have an 07 Fit, tires are from America's tires with warranty and( 60 mile tire warranty ) i have had nails/screws in 2 tires replace at 20k and 30k, same type tires, no difference. when it came time to replace, i replaced 2 tires that were at 75k and the other 2 stayed on. never knew any difference except at tire change from ware. i use americas tires due to discout tires and americas tires owned by the same company and are located in states i go to. .

 

Tire diameter tread to tread is the critical number, not tread depth. Brand to brand diameters vary but should not confuse pressure warning or ABS functions.
I'm a huge Micheln fan. The tread depth on their cry recommended tire is huge, 7/16" or 14/32". When time to change all 4, these tires are still a good value in wear and safety.