Is traction and rolling resistance a trade off?

[ledslinger]

I was reading about loss of fuel mileage with Michelin tires compared to the set they replaced. I faced this on my 2003 Silverado when I replaced the OEM Goodyear Wranglers. I lost at least one MPG, maybe up to 2. I have much more traction with the Michelins, and the increased safety outweighs the fuel mileage hit.

Although tread design and compound influences traction more than rolling resistance, the tire carcass is likely the main design feature affecting the tradeoff. It may be that a tire that has good traction has a bigger footprint that requires the tire to flex more eating up efficiency.

 

[440Magnum]

I suspect its not straight-line traction that decreases with rolling resistance, but handling feel due to sidewall structural stability and maintaining the contact patch when the sidewalls are under stress.

 

[AdRock]

There can also be a difference in the actual weight of the tire. The difference of a few pounds between rim weights can make a difference. A heavier tire will do the same thing. So imagine a tire that's a little heavier, has a larger contact patch, and grips the road better. Add that stuff up and I could see a 2mpg difference being possible.

 

[Kawiguy454]

I think you're on the right track. Thinner less structured tread and or sidewalls have less efficiency loss while rolling. But as soon as you demand performance they distort easily losing grip.

Years ago you remember the Firestone issue on explorer. A failed attempt to increase mileage with flimsy tires. It became a problem when the tires had very small defects.

 

[JOD]

Originally Posted By: ledslinger

Although tread design and compound influences traction more than rolling resistance, the tire carcass is likely the main design feature affecting the tradeoff. It may be that a tire that has good traction has a bigger footprint that requires the tire to flex more eating up efficiency.


No. In fact, the opposite is actually the case. All else equal, tires that have a more flexible carcass are going to have lower Crr, since there will be less energy loss due to hystersis with the more flexible carcass.

The reason folks typically notice a drop in fuel economy when they get new tires is that 1) less tread=lower Crr and 2) the odometer is over-reporting with worn tires.

 

[WobblyElvis]

I put cooper low rolling resistance tires on my 06 Malibu and it glides so well it changed how I drive. I noticed no problems with handling or braking but I'm a very conservative driver. They are now about 70% worn out and they are noisy. Undecided if I would buy them again.

 

[mrsilv04]

I don't think one can ever have too much traction.

The problem was, I had way too little of it when I was stupid enough to have a set of overpriced Michelin LTX's on my Silverado.

 

[HTSS_TR]

I think there is a trade off between traction and rolling resistance. There are some brands that has lower and higher speed rated of the same model. One of them is Cooper CS5 Ultra Touring, some sizes are available in both H and V rated. The V rated has better traction also shorter braking distance than H rated, but it suffers a little in MPG.

Cooper CS5 Grand Touring has some sizes in both T and H rated, again H rated has more traction with lower MPG than T rated.

Comparing different brands and/or models is not valid.

 

[CapriRacer]

Is traction and rolling resistance a trade off?

Yes, but it's a lot more complicated than that!!

Long version:

Barry's Tire Tech - Rolling Resistance and Fuel Economy

Barry's Tire Tech - Rolling Resistance and Fuel Economy 2

Short Version:

MOST of a tire’s rolling resistance is due to the tread. The tread has the most mass and changes there have huge effects.

When it comes to tread compound, there is a 3 way relationship between treadwear, traction, and rolling resistance. In order to get better properties in one area, one or both of the other areas has to be sacrificed.

More tread rubber means more rolling resistance. Not only does that mean that All Terrain tires will have more RR than All Season tires, it also means worn out tires have better RR than new ones (all other things being equal).

Casing stiffness hardly plays a role in RR – except to say that inflation pressure does play a part in that more inflation pressure stiffens the casing. Put another way, a tire with good handling characteristics (which also mean it doesn’t ride very well), may or may not have good RR as the tread compound is the dominant player.

Original Equipment (OE) tires - the ones that come on new cars from the assembly plant - have RR as an important feature as the vehicle MUST have a fuel economy sticker. As a result, many people experience poor treadwear and/or poor traction from these tires - AND they will also experience a loss of fuel economy when they change those tires out.

 

[TiredTrucker]

Can't speak to auto/pickup tires, but for commercial truck tires, rolling resistance is a serious consideration. That is why I use Michelin 445/50R22.5 wide base drive tires. A simple 1/10th mpg increase on a commercial semi truck is roughly $600-700 a year in fuel savings. A full mpg increase, and one is basically offsetting any tire price and getting free tires! But the RR is published data readily available for comparison purposes between brands and tire models on commercial tires. Would be nice to see similar comparison data on auto/pickup tires to make a more informed choice. While I will allow only Michelins on my commercial trucks, my pickup came with Michelin LTX's, and I am not all that joyous over them. I suppose if my 2500 was only used as a car on steroids on hard surface roads all the time, I might be more of a fan. Not developing a fondness for them in the rural farm type situation they are used in.

As a side by side comparison, the Michelin 445/50R22.5 XDN2, a more aggressive tire, has a RR of about 130. A 445/50R22.5 Line Energy tire is more tame on tread design and has RR of 99. Both use the very same cases. Only the tread design and compounds used differs. That is per Michelin data themselves. Recommended tire pressure based on load is identical between the tires. So at least in the same brand and similar tires, I would say the tread design is the primary reason for good or poor rolling resistance.