...…. So, I do have a question or need for clarification. If I'm understanding correctly, the tire that came as OE on my car, may not be the same as the tire I receive if I replace my tires down the road with same exact tires. My 2019 Kia Sorrento came with 235/55/19 Kumho Crugen Premium A/S tires. In a few years if I buy that same tire, it may not be quite as good as the tires that I now have from the factory? ……
As usual, the answer is a bit more complicated than that.
As long as the tire is being supplied to the vehicle manufacturer, there will likely be identical tires available at the tire dealer - albeit, not quite as good qualitywise.
HOWEVER, once the tires are no longer being supplied, it is likely the tire will revert to replacement market specs - in other words, better wear, but worse rolling resistance. It will take some time before the old, OEM stock is used up - say a year - and after that the tire at the tire dealer will be the replacement market spec tire.
EXCEPTION: GM requires its tire suppliers to supply OEM tires to the replacement market for 3 years AFTER the tire is no longer supplied to GM. Usually this takes the form of enough overrun to supply the expect demand - and sometimes the demand is more than expected and the tire supply dries up after 2 years. (Remember when I said the company I worked for tested tires in their warehouse for aging and found that tires 3 years old were not significantly different than freshly made tires? They did this because of this GM requirement.)
Please note: Tires that are supplied to GM have to have a TPC logo branded on the sidewall. So even those tires that GM requires to be available for 3 years have to have that logo as well.
……….. I find it interesting that you mention 'tight balance' for OEM tires vs downstream. I have always noticed over the years that the best balance jobs on tires were always the tires that came on the car (I'm talking new cars). It never occurred to me that it may be the tire that was better balanced, as opposed to the 'balance job'. Replacement tires were never balanced quite as well as the originals. …….
Well …… Ah ...…. It's like this.
Tight balance specs only mean that less weight is applied. Once a tire (and wheel) is balanced, it is balanced. It's only when a tire is not balanced properly, that you might feel a vibration, HOWEVER, tires also have uniformity issues (think out-of-round and you'll be close) - and that is probably what you are referring to.
Yes, the OEM specs for uniformity are tighter than the replacement market specs - sometimes quite tighter. That's because the OEM doesn't want the vehicle coming back for a silly thing like a vibration.
But a new vehicle is tight and any vibration is accentuated. Once a vehicle puts some miles on, it loosens up and not only can it tolerate more tire non-uniformity, there are also more vibrations going on that can disguise that vibration. The tire manufacturers know this, so their replacement market uniformity specs are not as tight.