> manufacturers could start selling cars with worse tires to bring down the average.

OEMs do the opposite already because their official MPG ratings are calculated using the OE tires. OE tires are sometimes criticized as prioritizing fuel economy too much at the expense of longevity and performance.

I don’t see a reason that a car manufacturer would be incentivized to help tire manufacturers sell the cheapest tires on the market

Car manufacturers watch the cost of every piece of the bill of materials. Cars compete on price, and the assortment of pieces which add perceived value to consumers. Outside of performance and very highend luxury cars, tires are an afterthought to the average car buyer.

Yes, which is why most optimize tires primarily for price, fuel economy, and NVH, because those are the things which a consumer notices the most when buying a vehicle: "what's the price, what's the EPA estimate, and did I like the test drive?"

Some manufacturers even source tires that have lower tread depths than typical replacement tires, in order to decrease noise and increase MPG at the direct detriment to tread life. Tesla is one of the manufacturers that does this, which is one exacerbating factor for their notoriously poor tire life. They literally come with less tire!

Toyota is infamous for offering special, nerfed versions of well-known tires on their new vehicles. You buy a Tacoma, you don’t get the Wildpeak AT4W, which is a very good all terrain tire. Instead, you get the Wildpeak AT4WA, which is a nerfed version with reduced tread depth that is quieter and more efficient than the real AT4W but less capable and wears out faster.

When buying tires as an average Joe for an average car (like a Corolla or Camry) it seems like being an OEM tire is actually a badge of honor for a tire. The reason is that that's the tire that they report MPG with and that you have on the car when you test drive it, so manufacturers care about ride quality and efficiency in the OEM tire. There's a lot of tires that are cheaper than OEM tires and they perform worse.

> My nose for unintended consequences says manufacturers could start selling cars with worse tires to bring down the average.

They won't want to do that because it'll hurt their advertised mileage/range.

This is aimed at the different incentives between selling tires to manufacturers (make sure mileage is good, balance that against raw cost) vs direct to consumers (up front cost is king).

There are doubtless still some potential loopholes that will be explored, though some of the most obvious (like reducing tread depth, mentioned here, appear to have been considered already: https://www.roadandtrack.com/news/a71509031/california-tire-... ). It doesn't appear to be that naive.

It's also something that's hard to find info on when shopping for tires, so more transparency should help consumers.

These calculations cannot possibly be true. That extra cost is way too small when tires have such a wide range of prices.

the original tires on my 2016 mazda 6 I bought new from a dealer in California were quite bad. Dunlop something. Bad on wet, okay on dry, lasted for short time. Replaced them after 2 years if I recall correctly. I wonder if original tires are any better 10 years later...

>My nose for unintended consequences says manufacturers could start selling cars with worse tires to bring down the average.

They already do. They mostly do it for handling and NVH though. And tire makers compete pretty seriously to be the OEM tire on a given car because it's a guaranteed-ish number of sales plus subsequent sales from all the people who just buy the same thing because clearly those work fine why think about it.