Interesting thing a Bridgestone/Firestone Engineer told me

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Basically he told me that factory line tires are actually different from the same model bought at outside merchants.

He said they are 99% percent the same but do contain manafacturer specific differences... ie mpg, handling, etc.

For example a factory set of Goodyear GA's are somehow different from ones you pick up at a local or online retailer.

Perhaps this somehow makes sense perhaps that I have noticed better wear fron exact replacement branded tires vs the factory stock ones?

So I pass this startling revelation to the board for review
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I think what you were trying to say was this:

Tires supplied to vehicle manufacturers are different than tires supplied to tire dealers and other retail outlets.

True.

Vehicle manufacturers purchase so many tires of a given size, they found they could dictate the performance characteristics to the tire manufacturer. On the positive side, this means the tire supplied is well tuned to the vehicle (usually), but on the negative side, there may be some characteristics that are compromised in favor of the vehicle manufacturer.

For example: Since each vehicle manufacturer has to meet a fuel economy standard, most tires supplied have improved rolling resistance. This is done at the sacrifice of treadwear and wet traction.

Here's where is gets tricky:

Many Original Equipment tires - tires supplied to vehicle manufacturers - have the same name as a regular line of tires. The example above - "Eagle GA" - is a good one. It means that these tires behave differently and it's different for each size.

That also means that anyone doing testing should be careful to avoid comparisons where OE tires are involved. (unless that is the point of the test) Further, any rating of tires has to consider these tires as a different line.

Here's what I draw from this:

1) Unless Consumer Reports specifically avoids testing OE tires, their comparisons are suspect.
2) Many consumer tire ratings at Tire Rack are dissing OE tires and that clouds the true performance of the rest of the line.

Hope this helps.
 
Subject: OE Tires

I have heard the manufacture wants a soft ride.He will compromise what ever it takes to achieve this.
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the tire rack at least used to display three lettrs after some tire sizes in their magazine adds. For example, toy, BMW, lex, etc.

I always thouht those tires were OE line replacements, compared to often sane-size and model tires without the three little letters.

JMH
 
quote:

Originally posted by CapriRacer:
For example: Since each vehicle manufacturer has to meet a fuel economy standard, most tires supplied have improved rolling resistance. This is done at the sacrifice of treadwear and wet traction.

Just a small note. Generally, as rolling resistance decreases, treadwear increases. A tire that sheds a lot of rubber just rolling down the highway is likely creating a lot of friction and probably doesn't roll that easily. I'd agree on the traction part (wet OR dry).
 
Kevm14,

It's a little difficult to tell, but I think you were saying that tires with good rolling resistance (good fuel economy) have good treadwear.

Not true!!

As a tire engineer, I can tell you the rubber chemists play with the treadwear/RR/traction balance all the time, trying to meet the OEM's RR and traction requirements while also trying to minimize the treadwear impact.

As a reality check, clearly OEM's would want low RR making it easier for them to meet their CAFE requirements, but none of them offer tires with a 700 UTQG rating.

Perhaps the confusion is the many high performance tires, which have good grip, also have poor RR AND low treadwear ratings. In this case, its the traction that is dominating the equation, not to mention the nylon overlays that improve high speed capability (more tire weight = higher RR values)

Hope this helps.
 
A former GM suspension engineer told me that GM demands that the tires supplied to them have a much tighter balance tolerance that those supplied in the replacement market. They dont want buyers of new cars to feel any vibration at all. This also allows them to use fewer and smaller wheel weights.
 
It seems like everyone remembers how long their OEM set of tires lasted. It helps that the odometer started at zero and they remember seeing the tire guy at 35k. New tires were probably the first thing to wear out, too.

I just don't expect OE tires to last that long; I think most of the ride, handling, mpg compromises wind up with less tread wear. It's funny most people take it for granted the first set of tires won't last very long and aren't too upset by it as far as brand loyalty is concerned.
 
quote:

Originally posted by CapriRacer:
For example: Since each vehicle manufacturer has to meet a fuel economy standard, most tires supplied have improved rolling resistance. This is done at the sacrifice of treadwear and wet traction.

Absolutely true. I was a victim of Honda's relentless pursuit of lowered fleet MPG, in my case, a set of GY HP Wrangler's that were worn to 4/32 in 17,000 miles
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("advertised" warranty was 45,000 miles). I was able to get a substantial pro-rated adjustment on some new Dunlops
grin.gif
. The OEM HP's were garbage in all respects and didn't even look like the retail HP's. Manufacturers just hope most consumers won't pursue such an adjustment.
 
quote:

Originally posted by Jimbo:
They dont want buyers of new cars to feel any vibration at all.

Which explains why GM produces vehicles that are incredibly sensitive to vibrations (Sarcasm!)

Of all the vehicle maufacturers, they seem to be the worse for a) producing sensitive vehicles and b) not fixing the problems that cause their vehicle to be sensitive.
 
quote:

Originally posted by CapriRacer:

quote:

Originally posted by Jimbo:
They dont want buyers of new cars to feel any vibration at all.

Which explains why GM produces vehicles that are incredibly sensitive to vibrations (Sarcasm!)

Of all the vehicle maufacturers, they seem to be the worse for a) producing sensitive vehicles and b) not fixing the problems that cause their vehicle to be sensitive.


Heheh, although this is O/T that would explain why a friend of mine has a '99 Olds Alero that makes this HORRIBLE warbling, metallic noise when you take corners. It makes you think the bearings are totally gone or the wheel is about to wobble off the studs! It's gotten worse over time and they "can't find anything wrong" and blamed the tires.
rolleyes.gif



On the subject of OEM tires, I find this admission interesting. Among the list of famously disliked OEM tires is the Bridgestone Potenza RE92... I guess this would explain this and also why many other OEM tires tend to suck.

It sure throws a monkey wrench into trying to figure out if the tires a car comes with are any good or not.... For instance, I found it impressive to read that the Hyundai Tiburon was equipped with Pilot Sport A/S tires. Now who knows if they're that great in real life though....
 
The Uniroyals that were OE on my Chevy truck lasted too long. Rock hard with no grip, I finally gave up at 60,000 and thought I had found the ideal replacement tire, Firestone Wilderness AT!
 
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