IRRESISTABLE

Fuel Max-fitted Prius at the Helios House GOODYEAR'S LOW-ROLLING RESISTANCE FUEL MAX TIRE By Roy Nakano The Assurance has proven to be a popular line of tires for Goodyear. The Assurance Comfortred has been sought out by those seeking a comfortable ride, whereas the premium Assurance Tripletred is among the highest rated family car-application tires for its combination of high performance in both dry and wet weather conditions. The Assurance Fuel Max answers the call for those seeking optimum fuel mileage in a passenger car tire without the usual compromises associated with such tires. Goodyear says the Assurance Fuel Max features a fuel-saving tread compound that helps reduce energy loss as the tire rolls. Wet and dry tread zones are said to enhance all-season traction. The basic formula for creating a high fuel mileage tire has been around for eons. High fuel mileage is highly dependent on low rolling resistance. The lower the rolling resistance, the less energy that has to be generated (i.e., fuel burned) in order to overcome that resistance. “People have been building tires designed for fuel economy for quite some time by mixing silica into the tread compound which serves to reduce the friction between tire and road.” says Barret Hudson of Green Collar Operations – an Austin, Texas-based company that specializes in performing energy efficiency improvements.

According to Hudson, silica-based tires do dramatically reduce rolling resistance, but they suffer from decreased tread life compared to traditional carbon black tires. This has been true with tires like Goodyear’s own Integrity tire, which came as standard equipment on Toyota’s second-generation Prius. The poor tread wear often motivated Prius owners to look elsewhere when it came time to replace tires (Goodyear’s Assurance Tripletred and Michelin’s Energy and HydroEdge remain popular replacements for , For the Fuel Max tire, Goodyear does utilize silica , but Hudson believes that Goodyear has come up with a compound that interacts with the silica in such a way as to increase overall tread strength. “Goodyear does not make it clear exactly how this is achieved,” says Hudson. “But they do hint that it has something to do with improving the overall dispersion of the silica in the tread of the Fuel Max tires.” For our evaluation of the Fuel Max tire, we used our Project Prius vehicle which heretofore had been running Tripletred rubber. The stock tires on the second-generation Prius are Goodyear Integrity P185/65R15. The Tripletreds were P195/60R15, which maintained the same overall diameter, but carried a slightly wider footprint. The use of the Tripletred over the stock Integrity tires resulted in a slight decrease in average gas mileage (approximately 1.5 miles per gallon overall), but significantly better handling. The P195/60R15 Tripletreds are credited with avoiding an accident on the freeway, when we had to make an emergency maneuver to avoid a garbage can in one of the lanes. Finally, the wider tread of the Tripletreds also gave the car a more attractive stance—making our Prius look a little less dorky than with the skinny stock Integrity rubber.

At the AQMD For this new comparison, we decided to stay with the same profile as the Tripletreds: P195/60R15. By doing this, we hope to retain the good handling characteristics of the Tripletred while bringing the fuel economy closer to what we got with the skinnier P185/65R15 Integrity tires. The results were pleasantly as hoped. Gas mileage went up and average of 1.25 miles per gallon. Not quite up to the skinnier Integrity tires, but a distinct improvement over the old rubber. Handling in wet and dry conditions was still significantly better than the stock tires, albeit without the cornering tenacity of the Tripletreds. The tires brokes loose a lot easier, but in a rather predictable fashion—the higher the speed, the greater the drift. Unlike some tires that have enormous grip, then widely break loose at a certain point, the Fuel Max tires give you plenty of warning when the grip starts to loosen. The low rolling resistance of the Goodyear Assurance Fuel Max produces one other benefit: These are the quietest tires we have ever tested. No tire in recent memory produces so little sound, making the interior noise level in the Prius significantly quieter than even with the stock Integrity tires. This may explain why Toyota decided to make the new Fuel Max the original equipment tire for the third-generation Prius. It’s not just Toyota, however. General Motors announced that the Goodyear Assurance Fuel Max will also be the original equipment tire for the 2011 Chevrolet Volt electric car. These two moves speak volumes about the tire.

VITAL STATISTICS: Name of tire: Goodyear Assurance Fuel Max Price: $139.99 Product Dimensions: 24.2 x 7.9 x 24.2 inches ; 17 pounds Shipping Weight: 28 pounds (View shipping rates and policies) ASIN: B002RNBDPO Section Width: 195 Rim Diameter: 15 inches Load Index Rating: 87 Speed Rating: H UTQG: 580-A-A Item Weight: 17 Pounds Height: 61.5 centimeters Length: 61.5 centimeters Width: 20.1 centimeters Features: * Fuel-Saving Tread Compound - Helps reduce energy loss as the tire rolls * Wet Tread Zone with Dual Aquachannel Grooves * Dry Tread Zone with Solid Shoulder Blocks * Zig-Zagging Micro Grooves and Center Tread Notches * Circumferential Shoulder Grooves - Help promote even treadwear Source: Manufacturer loan For more information about Goodyear tires, go to goodyeartires.com