Actually, LRR tires can improve traction over more conventional methods of tire construction. This apparent contradiction is true because LRR tires are more flexible, react (distort to increase footprint) to forces of braking, acceleration and maneuvering more readily and produce less heat when they distort.

The improved fuel economy is acheived when the tire is not distorted (steady state condition) and an FE improvement of 4-7 percent is possible when LRR tires are used. This is acheived by using materials and tread designs that reduce the 'squirm' frictions that result from the tire spreading as it makes contact with the road and then returning to it's original shape when breaking contact.

The squirm has nothing to do with scrubbing, which is what takes place between the rubber and the road. Instead, it is almost entirely from the flexing of the rubber and (mostly) the elastomers in the tire. This includes the binder between the casing, inner (tube) liner and between the casing and tread, all of which flex and absorb energy that must be released as heat. This squuirming friction in conventional tires creates heat that changes the tire pressure over a larger range. Reducing squirm in LRR tires lowers tire friction without loss of road contact, narrows the heat and permits the tire to operate at the more constant pressures that result from a narrower heat range.

The trade-off for LRR tires is not traction. It is cost (they are more expensive to manufacture), and in the case of the earlier ones life cycle because the materials used were softer. Later designs for LRR tires have dramatically improved tire wear and tire life.

Here are a few sources (there are many more):
http://www.michelin.com/corporate/fr...e=PAG_AXE_RECH

http://www.cabot-corp.com/cws/busine...6TruckTire.pdf

http://www.oeconline.org/livinggreen...ofriendlytires

http://sheldonbrown.com/brandt/rolli...e-tubular.html

It is the ignorant among us that will eventually destroy us all.

Both my '07 TCH and '07 XLE-V6 came with Bridgestone Turanza EL400 which have A - A - 260 ratings. FWIW.

Huh.... OK, so ignore what I said about the Bridgestones. The site is confusing - they appear to list multiple tires for the Camry Hybrid. interestingly, they list the ER33 as the OE tire for the TCH, although schmidtj got the EL400.

The 440AA rating is however correct for the Michelin.

--My hybrid came home!--
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Randy