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A word of caution
A word of caution:
LRR is a relative term, not an absolute term. What it means is 'compared to tires with similar treadwear and traction characteristics, the LRR tire will deliver better fuel economy.
The basic principle is that treadwear,, traction, and rolling resistance form a technology triangle. To get better values in one area, one (or both) of the other areas have to be sacrificed.
HOWEVER, some small changes can be made to this triangle by advances in rubber chemistry - which is what the "LRR" is trying to point out. But those changes are small compared to the changes available from the triangle.
So let's see how this work.
The Bridgestone B381 is reported to be have extremely low rolling resistance. It's UTQG rating is 260 A B. The reports are that it has traction AND wear issues - although Tire Rack's survey doesn't seem to support his.
The Goodyear ComforTred is rated 700 A B. Interestingly, the surveys don't say it is delivering much better wear. (7.5 vs 7.1) However, it is clear the traction is better - even though the UTQG traction ratings are the same!
The Michelin Defender is rated 820 A B. But since it is in a different category, you have to be careful about the survey ratings. However, the tire is rated very highly for both treadwear and traction (even though it also has the same traction rating as both the ComforTred and the B381.)
So be very careful trying to do this math. The true RR values are unknown - and LRR doesn't mean what is appears to mean.
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