Check out my page on tires and fuel economy:
http://barrystiretech.com/rrandfe.htmlAlso a followup:
http://barrystiretech.com/rrandfe2.htmlBottomline:
Tires can have a large effect on fuel economy that is mostly depedent on how you drive. Do a lot of country driving and the effect is larger than if you do a lot of city driving - but the effect is limited by the amount that tires contribute to fuel economy - 7% max!
Also, tread compounds are part of a three way technology triangle - treadwear, traction, and fuel economy. To get better results in one area, you have to sacrifice one or more of the others areas.
The exception to this is that small tweaks can be made the alterer this relationship slightly. The addition of silica to the tread compound is one of those.
People need to be aware that all other things being equal new tires get better fuel economy than worn out tires.
Plus, vehicle manufacturers emphasize fuel economy at the sacrifice of treadwear and/or traction, which is why OE tires (tires that come on new cars) have such a poor reputation. It's not that they are poor quality - it's that the design goals are different. Replacement market tires are expected to deliver good wear, so they are designed the opposite.
So ..... When you change from a set of worn out OE tires, you should expect a loss in fuel economy - partially because of worn vs new, partially because of OE vs replacement market, and this is especially true if you pick a tires with high treadwear ratings.
And lastly, LRR (Low Rolling Resistance) is a retailer applied term that is relative, not absolute. It was invented by retailers to try to indicate which tires give better fuel economy - BUT - it means better fuel economy compared to tires of similar wear and traction levels. It is quite likely that a tire not designated *LRR* would get better fuel economy than an LRR variety with a large UTQG treadwear rating.
