Low rolling resistance tires?

[srivett]

I am looking for a set of low rolling resistance tires for my car. I've got a set of winter wheels and tires so these tires can be summer tires as long as they are safe for reasonable driving. What is a good option that will pay for itself in diesel highway economy?

I'm supposed to run 175/70/13s but am willing to try 155s or 165s for a bit of height/circumfrence advantage. You gotta love the low prices for 13" tires.

I am not concerned about speedo error, my car indicates 385K km and is atleast 10% too generous. My transmission is geared too low so I won't be lugging with taller tires. Also, VW diesels have gotten better mileage with taller transmissions in the past. ie. 1200km/52 litres versus 1000km

Thanks, Steve

 

[seotaji]

low rolling resistance = low traction, at least for me.

michellin mxv4 plus have low ratings for everything, but i have no idea if they are in your size.

you should see what the toyota prius uses, since they use small 13"-14" wheels.

 

[JeepZJ4.0]

quote:

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Originally posted by seotaji:
low rolling resistance = low traction, at least for me.

michellin mxv4 plus have low ratings for everything, but i have no idea if they are in your size.

you should see what the toyota prius uses, since they use small 13"-14" wheels.

---

15 inch rims covered with 185/65SR15 Goodyear Integrity tires... Integrity ---> really poor traction from these tires.

 

[srivett]

I'm thinking more along the lines of tire construction like bias vs. radial. I'd also think lighter, narrower tires would belp a bit without compromising safety.

Around here nobody needs performance tires. I deliver Pizza with my 52HP diesel and I dust everybody off of the lights so if they have performance tires they are wasting their money. I clip along at 20 over the limit so the fastest I'll see in a day is 110 km/hr. All the performance I'll need is to get me stopped in the wet or dry without losing control. Also, tires that would be scary on a high performance car that can light up its tires during every shift should be just fine on my car.

Cheers, Steve

 

[Quattro Pete]

srivett, in your case I would generally look for tires with a very high treadwear index, because that means long wear, and long wear means poor grip, and poor grip means low rolling resistance. I am simplifying here, but I believe that is generally how it works.

So, something like Michelin Harmony or Bridgestone Turanza LS-T should fit your bill, just quickly scanning tirerack.

As far as using narrower width - it's your call. You might get some additional reduction in rolling resistance at the expense of diminished highway speed stability. Also be sure to check that their load index meets your car manufacturer requirements. If the load index is too small, the tire will heat up more and may lead to faster wear or even a blow-out in extreme cases.

 

[CapriRacer]

OK, guys, let me try to explain what is what with regard to rolling resistance in tires.

Mass (weight) = rolling resistance. The heavier the tire, the lower the fuel economy.

Since the tread is the heaviest component in a tire, the tread compound has a great effect on RR.

There are three things that can get traded off when it comes to tread compound: treadwear, rolling resistance and traction (especially wet traction). So if you want low RR values, you have to sacrifice traction and / or treadwear. For example, OE tires, which the OEM's want to have low RR values, are generally low treadwear and / or low traction. Read the ratings on OE tires and that's always what the complaints are about.

BTW, this does not mean that tires with low treadwear ratings have low RR - might be true, might not. Same for low traction.

But there are things that affect wet traction and wear that don't affect RR. For example, lots of sipes is good for wet traction, but bad for wear, and RR is pretty much the same.

So how do you pick tires with low RR values?

First stay away from high speed rated tires - more material = more mass = higher RR. That also eliminates that problem of confusing high grip/low treadwear with high RR

Second, find a tire line that specifically mentions fuel economy. But be aware that most tire manufacturers don't publish RR ratings. Why? It doesn't help sell tires (except for those few interested in the subject).

So if you can't find a tire that is designed for low RR, then your best bet is to find an OE tire (note - that size has to be OE, not part of the line)

BUT!!!

There is something that everyone has control over that has more effect on RR than the tire itself - inflation pressure. Higher is better.

So in this particular case:

1) The change in tire size isn't going to have a major effect on RR, especially since a P175/70R13's aren't OE anymore and the comparable 75 and 80 series tires are more likely to be produced in the cheap versions only, meaning that the tires won't have the exotic, and expensive, tread compounds.

2) S speed rating. This means that the "20 over the limit" has got to go!! (more fuel consumed and a larger risk relative to the speed rating)

3) Use as high an inflation pressure as you can feel comfortable about the traction (which means some tests doing panic stops).

Hope this helps.

[ December 22, 2004, 08:54 AM: Message edited by: CapriRacer ]

 

[JHZR2]

I am happy with the pirelli p6 four seasons on my 04 saab. They are low RR, but get excellent traction, and have a pretty hard rubber compound with a continuous tread band down the center for better wear and quieter operation. That said, I dont know if you can get them.

Another good one is the continental ecoplus (contitouringcontact).

Your tire size makes it really tough to find a modern tire with the combination of good grip and low RR. Id do what others have said and look for one with a harder rubber compound (determined because the treadwear rating is very high), which when inflated reasonably high, ought to minimize RR.

JMH

 

[rpn453]

Sounds like the best option for you is to go with the cheapest tires you can find and run them at relatively high pressure. This will give you low rolling resistance. Look at the tread pattern too. If it looks smooth (small gaps, continuous strip down the middle, etc.) then it will probably roll smooth. A high treadwear rating is also probably something you'd want in a tire, but make sure it still has at least a traction rating of "A".

If you really want to save a little fuel and go with narrower tires you could go 155/80R13. These are a common size and are only 0.5% bigger in diameter than the 175's so your speedo would still be pretty much right on. I wouldn't though, and I actually recommend that people with factory 155/80R13's go with the 175/70R13's when replacing tires. The ride and handling will be much worse on such narrow tires.

 

[TR3-2001SE]

The Bridgestone RE92 is used on the Honda Hyb. and is the only one recognized as low RR. It was also used on several solor powered cars. It was used in a 165/65/14 size but also comes in a 165/65/13 which should be perfect for you. Wish tire manufactures would start putting RR ratings on their tires. Michlen zx was also a low RR tire which was popular in the 60-70's.