I am going by what I see posted as a consumer. The specs I quoted are identical. Your statement : "but the traction, wear, grip, ride, and handling (set by the vehicle manufacturer) could be COMPLETELY different." is where I was keying into, as there is nothing noted on the website stating any kind of difference between the two other than "OEM", which means little to the other tire's differences. And like the above poster stated, the reviews are lumped, making it even harder to distinguish the two. I was just trying to figure out what9if any) differences were between them, and why those differences were not noted. AS a consumer, how am I supposed to know the difference? Does that make any sense, as it's hard to explain for me?
Oh!
You want to know what the performance differences are between the 2? I wish you had said that in the beginning.
First, OE tires are unique to themselves. Even tires of the same name , whether going to the same vehicle manufacturer or not, whether even going to the same platform, are different than all the other OE tires. That's because the specs the vehicle manufacturer sets are unique and aren't repeated (for reasons I don't understand).
Then there is the issue that the vehicle specs are trade secrets (for the vehicle manufacturer) and they don't want anyone sharing those specs. Put another way, all those OE tires in that lineup we are referring to are each different with only isolated bits of commonality.
Bottomline: Consumers aren't going to find out what those specs are and therefore, what the differences between an OE tire and the equivalent aftermarket tire is. You only get hints. In this case the hints aren't there.
So allow me to go down the list of performance parameters and explain:
But before I do, you should be aware that as a general rule OE tires are designed to give better rolling resistance and that is obtained by sacrificing treadwear and/or traction. The vehicle manufacturers have to publish a fuel economy value and tires play a role in that and the OEM's take advantage of that and the fact that they (the OEM's) don't buy a mileage warranty on tires, so they don't care abut tire wear even though the consumer does! That's why OE tires have the reputation of being poor quality.
Rolling Resistance: There are many RR tests, and they give different results. About 10 years ago, there was a government proposal for a regulation for publishing RR values. There were some issues with the proposed regulation - it was unworkable. It was withdrawn and nothing has been proposed since. Without that, RR between tires can not be compared.
Treadwear: That's what the UTQG rating was supposed to be. The quirk here is that tire manufacturers are NOT allowed to overstate the results of the test, but they ARE allowed to understate them. That is what is going on here - the aftermarket tire was understated to the point where the OE tire can still have the same rating.
Traction: The UTQG traction rating was also supposed to address this. But traction tests are highly variable. Not only does it depend on what surface you test on, but ambient conditions greatly affect the test results. Plus you can get reversals depending on the test surface. The UTQG is a wet traction test and it only has limited correlation to dry traction - and, of course, no correlation to snow traction.
OTOH, there is a universal snow traction test and passing that test allows tire manufacturers to use the Mountain/Snowflake symbol. However, lack of the symbol might mean the tire was never tested.
Ride and handling are both touchy-feely kind of tests. The tests are always a comparison test - and both parameters are usually done at the same time. Further, soft riding tires aren't great handling tires and vice versa.
So there you go. It's a shame that consumers don't have the complete tools to decide, but it is the way it is - and not likely to change soon.
