Fuel Economy Standards for Tires in the US

[CapriRacer]

NHTSA (National Highway and Traffic Safety Administration) was originally supposed to publish a rule concerning the publication of rolling resistance data for tires in 2010, based on a mandate from the US Congress in 2007. There was a large problem with what they published (short version: It was unworkable!). So they went back to the drawing board.

Eventually they came back saying they would publish a rule in 2012. That date came and went.

Earlier, I found a publication of new rules being worked on by the US Federal government:

https://www.transportation.gov/regul...nt-rulemakings

Back when I found this report, the regulation for tire fuel economy had a future publication date of Aug, 2018. The report has been updated several times since then, and the latest date is March 2020 - and that has come and gone without even a status update!

I am putting this here to remind folks (and me, too!) that there is something coming and where to go to find the status.

 

[skyactiv]

Don't tires in Europe have such ratings already?

 

[Jetronic]

for a decade already, IIRC

 

[skyactiv]

Unfortunately, most of the tires on the other side of the pond are different and not available here.

Polish Goodyear site shows the fuel rating as C on this tire. The USD is $109.00 for the 205/55/16.

 

[Jetronic]

C is a good rating for a 3PMSF tyre

 

[DuckRyder]

This would be a good thing if the .GOV can manage to make it workable/comparablereal world rating...

 

[Quattro Pete]

The treadwear index is a joke, and we've had it for how many decades now?

Call me skeptic, but I'm not holding my breath for this fuel economy rating.

 

[SZR48207]

The treadwear index is a joke, and we've had it for how many decades now?

Call me skeptic, but I'm not holding my breath for this fuel economy rating.

Even something like tire pressure is highly debated, so yeah.. the rating won't mean much.

 

[JimPghPA]

I remember about 20 years ago after there was talk about being concerned about tire rolling resistance one of my relatives bought a new Crown-Vic and the first time they drove it in the rain the new Michelins' that came with it had soooo much silicon in the rubber that when they hit the brake to stop they slid all the way through an intersection on an asphalt road that was only a year or so old, and they were not going too fast. They were lucky and there were no other vehicles in that intersection at that time. They got rid of those tires the next day.

I hope tire designers remember the mistakes they made in the past. There is such a thing as going too far with reducing rolling resistance at the cost of tires without enough traction to be safe.

 

[Jetronic]

they haven't, really. There's a definitive reduction in wet traction for eco tyres. Working as a dealer tech I get to test drive multiple similar cars a day, and the eco tyres are not good in that regard. Not as bad as the ones from 25 years ago but still.

 

[SZR48207]

They could always spec skinnier wheels and tires since that also reduces rolling resistance. Not so great for ride quality, but suspension tweaks could maybe address that.

But you can bet that consumers would just turn around and slap the widest wheels and chunkiest tires on that they could find. And then those consumers would complain the gas mileage didn't match the Moroney sticker and there would be class action lawsuits.

Can't win!

 

[CapriRacer]

I remember about 20 years ago after there was talk about being concerned about tire rolling resistance one of my relatives bought a new Crown-Vic and the first time they drove it in the rain the new Michelins' that came with it had soooo much silicon in the rubber that when they hit the brake to stop they slid all the way through an intersection on an asphalt road that was only a year or so old, and they were not going too fast. They were lucky and there were no other vehicles in that intersection at that time. They got rid of those tires the next day.

I hope tire designers remember the mistakes they made in the past. There is such a thing as going too far with reducing rolling resistance at the cost of tires without enough traction to be safe.

Ah .... Mmmm .... Not exactly.

The problem you describe was created by the vehicle manufacturer's management. They design the tires because they write the specs. (OE tires) The aftermarket tires the tire manufacturers design with good RR are called LRR (see above discussion on the name) - and those don't have the traction problems the OE tires do.

And that is especially true for Japanese based vehicle manufacturers. The best I can tell is that they do their traction testing in Japan on native pavement - and they seem to ignore the differences in pavement in the US (and elsewhere.)

They could always spec skinnier wheels and tires since that also reduces rolling resistance. Not so great for ride quality, but suspension tweaks could maybe address that.

Ah .... Mmmm .... Not exactly.

The tires sizes with the best RR are those with the largest load carrying capacity. I discuss that here: Barry's Tire Tech: Follow up on Rolling Resistance and Fuel Economy

 

[JimPghPA]

I understand that vehicle manufacturers with high volume purchase may have enough clout to get tire manufacturers to custom design tires, and to be fair I remember well the intersection where the new Crown-Vic slid through the intersection and it is a down hill slope. Not one of the severe angles that some hills in Pittsburgh have, but not level. And the brake action they got when they tried to stop on that wet asphalt was terrible and dangerous and actually scary to say the least. And to them back then opening up the wallet for a new set of tires was not easy. They still had 3 kids living at home then. But it scared them enough to spring for a new set the next day.

The point was that any normal tire would have been able to stop the vehicle under the same conditions. But the set that came with the car was dangerous in wet weather.

You would think that the tire manufacturer would draw the line in how slippery a tire could be and tell the vehicle manufacturer where that limit was.

Kinda like Firestone should of told Ford that there is a limit to how high a profile a truck tire could have and still be safe.

 

[CapriRacer]

You would think that the tire manufacturer would draw the line in how slippery a tire could be and tell the vehicle manufacturer where that limit was.

Kinda like Firestone should of told Ford that there is a limit to how high a profile a truck tire could have and still be safe.

You'd like to think that, but that is just not how this works. The business relationship between a vehicle manufacturer and its suppliers has always been a top-down kind of thing and even the Ford Explorer/Firestone ATX thing only altered the relationship slightly. Before that there was incredible pressure to conform - after all, the business was millions of dollars. After that, they would at least listen to their suppliers before overrulling them.

 

[JimPghPA]

Look at how much the Firestone fiasco cost both in actual dollars and reputation.

 

[benjy]

had OE mich MXV energy tyres on my new 2001 JETTA, WORSE tyres ever in the rain + replaced before they were worn out!! there is NO ONE SIZE DOES ALL, + all tyres trade traction or wear or something between! todays tyres are better than ever as they should be for their $$$$!!