Question On Tire Description

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Was strolling through the TR website and came across the Michelin Primacy Tour tire size for my vehicle. I see there are two models of the same tire. The first, says OEM,
  • Size: 225/55R18 98V
  • DT Different Tread
  • Style: Blackwall
  • Eco Focus: Michelin Total Performance
  • Serv. Desc: 98VLoad Index 98= 1,653 lbs (750 kg) per tire
    Speed Rating “V”= 149 mph (240 kph)" id="serviceDescHelper255VR8PTASV2" style="outline: none; border: 0px; margin: 0px 6px 5px 2px; padding-right: 0px; padding-left: 0px; width: 15px; height: 15px; display: inline-block; vertical-align: middle; background-image: url("https://www.tirerack.com/images/css_elements/retail/icon-sprite.png"); cursor: pointer; background-position: -30px -1429px;">
  • UTQG: 540 A A
The second, is basically the same, except without “DT Different Tread”

  • Size: 225/55R18 98V
  • Style: Blackwall
  • Eco Focus: Michelin Total Performance
  • Serv. Desc: 98VLoad Index 98= 1,653 lbs (750 kg) per tire
    Speed Rating “V”= 149 mph (240 kph)" id="serviceDescHelper255VR8PTAS" style="outline: none; border: 0px; margin: 0px 6px 5px 2px; padding-right: 0px; padding-left: 0px; width: 15px; height: 15px; display: inline-block; vertical-align: middle; background-image: url("https://www.tirerack.com/images/css_elements/retail/icon-sprite.png"); cursor: pointer; background-position: -30px -1429px;">
  • UTQG: 540 A A

What‘s the difference in the tread (The pics show the identical tire on both)? They both cost the same. Ratings are duplicated.
 
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What it means is the photo is not exactly like the tire. Somewhere on the website, there should be a statement to that effect.

Further, OE tires are designed to the vehicle manufacturer's specs, not the tire manufacturer's specs. It is very likely that the tire has better rolling resistance, but worse wear and traction (dry, wet, show). The tire will also likely have different ride and handling qualities..
 
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I watched a tire test on YT once that gave a lot of details on certain tire brands. Sometimes tires spec'd by OEM will use a different compound in certain parts of the tread to increase performance or change wear patterns.
In other words they can put a harder compound on the edges and softer in the middle to overcome or accentuate performance of the tire on certain vehicles.
Mercedes sells MOE marked tires for example, even though they are Pirelli Cinturato P7's. MOE = Merc Original Equipment.
The S class will come with a comfort tread design for the same reason, marked differently on the sidewall.

 

Propflux01

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I get that the picture is the same (generic), but why would The tire be spec'd exactly the same, yet the only difference being a "different tread"? I can understand a different tire in itself, but the exact same specs? Would or should there be something noted in the "non OEM" tire that would distinguish it from the "OEM Tire"?
 
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I get that the picture is the same (generic), but why would The tire be spec'd exactly the same, yet the only difference being a "different tread"? I can understand a different tire in itself, but the exact same specs? Would or should there be something noted in the "non OEM" tire that would distinguish it from the "OEM Tire"?
First, the "specs" aren't the same. The load carrying capacity (set by the tire standardizing organization), the max inflation pressure (determined by the tire manufacturer), the UTQG ratings (also determined by the tire manufacturer) could all be the same, but the traction, wear, grip, ride, and handling (set by the vehicle manufacturer) could be COMPLETELY different.

Notice that the max pressure, tread depth, tire weight, tread width, and country of manufacture are all different.

As far as the non-OE tire: Usually it's the OE tire that is the oddball - and that why Tire Rack makes that kind of designation rather than the other way around. In this case, this line of tires appears to be a mix of OE and Non-OE - like it started out as a non-OE line and OE tires were added later.
 

Propflux01

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First, the "specs" aren't the same. The load carrying capacity (set by the tire standardizing organization), the max inflation pressure (determined by the tire manufacturer), the UTQG ratings (also determined by the tire manufacturer) could all be the same, but the traction, wear, grip, ride, and handling (set by the vehicle manufacturer) could be COMPLETELY different.

Notice that the max pressure, tread depth, tire weight, tread width, and country of manufacture are all different.

As far as the non-OE tire: Usually it's the OE tire that is the oddball - and that why Tire Rack makes that kind of designation rather than the other way around. In this case, this line of tires appears to be a mix of OE and Non-OE - like it started out as a non-OE line and OE tires were added later.
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?
 
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I have seen on the TR, the same exact tire listed 3 X with different prices(only by a few $) with all of the same spec. I asked the question to TR rep and I was told that they're listed 3X or even more due to being OE on so many different cars/brands. Choose the least expensive one I was also told. I'm sure that there are other scenarios.
 
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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.
 
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Sorry, I am just repeating myself.

When I was looking on the TR site to replace my tires(215-55-17) OE Michelin Primacy MXV4(93V), the TR listed my exact tire somewhere around 3 or 4 times, all being of the same size/speed rating (93V), treadler/temp etc. And all being a slightly different prices(by a few dollars).

And again as I mentioned above, the TR Rep told me that this is because of this particular size is OE(as well as others) on several brands/models and to chose the one with the lowest price...if I were to buy the Primacy MXV4 93V, in which I didn't buy the Michelin again @ $226/tire.

However, the TR also listed my size(215-55-17) in an aftermarket Michelin Primacy MXV4 of a (94V) speed rating as well. So, this can be confusing to many shoppers. And I'm sure that if I were to buy the 94V, I would have felt differences between this and the OE 93V.
 

Propflux01

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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.
Thank you. Well explained.
 
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