- Mud Flaps
- Engine Tuning
September 17, 2010
Grand Touring All-Season tires are designed to blend the smooth, quiet ride of a Passenger All-Season tire with the handling of a Performance All-Season tire, all while providing some year-round traction in moderate winter conditions. But admittedly, this can be a tight line to walk for tire designers as they strive to optimize both sides of the equation, where improvement on one side may mean a trade-off in the other.
Several new Grand Touring All-Season tires have debuted recently, so we conducted a Real World Road Ride and Performance Track Drive to find out how they compare with several staples from the category. Goodyear has just released the Assurance ComforTred Touring, which adds H- and V-speed rated sizes to build on the good ride quality of the original (primarily T-speed rated) Assurance ComforTred from the Passenger All-Season category, blending in some additional responsiveness and handling. Also new is the Michelin Primacy MXM4, designed to enhance traction and handling over previous-generation Michelin Pilot HX touring tires.
We compared the new Goodyear and Michelin tires with two popular options from the Grand Touring All-Season category, the Bridgestone Turanza Serenity (a very popular replacement option) and Continental ContiProContact (widely used as an Original Equipment fitment). Our evaluation used 2011 BMW E92 328i coupes fitted with new, full tread depth 205/55R16 tires mounted on 16x7.5" wheels.
What We Learned on the Road
Our 6.6-mile loop of expressway, state highway and county roads provides a great variety of road conditions that include city and highway speeds, smooth and coarse concrete, as well as new and patched asphalt. This route allows our team to experience noise comfort, ride quality and everyday handling, just as you would during your drive to school or work.
All four of the tires in our test delivered the refined road manners we expect from Grand Touring All-Season tires. The Michelin Primacy MXM4 did a good job softening the sharp edge of abrupt impacts, feeling taut but not harsh. The Goodyear Assurance ComforTred Touring was right behind, feeling almost as refined and controlled as the Primacy MXM4. The Continental ContiProContact and Bridgestone Turanza Serenity followed, both feeling a little less supple than the Primacy MXM4, allowing a bit more of the road's imperfections to be felt by the driver.
The Primacy MXM4 also delivered the quietest ride of the group, producing minimal tread noise and only a modest boom when encountering abrupt impacts. The Assurance ComforTred Touring also produced very little tread pattern noise, but did emit a bit more impact noise. The Turanza Serenity generated a little more overall tread noise than the Michelin and Goodyear tires, with the ContiProContact rounding out the group right behind the Bridgestone for overall noise levels.
Our team was somewhat divided as to which tire provided "better" road handling. The Assurance ComforTred touring provided quick initial steering response with a linear build up in cornering effort, while the Primacy MXM4 displayed a taut, stable feel when driving straight ahead, especially at highway speeds, but responded a little more slowly to initial steering inputs. The Turanza Serenity drove well, but didn't have the refined handling feel of the Michelin and Goodyear tires. The ContiProContact followed with steering response that was a little less precise than the others.
What We Learned on the Test Track
Our 1/3-mile per lap test track course includes 90-degree street corners, lane changes and simulated expressway ramps. Run in both dry and wet conditions, the test track allows our team to experience the traction, responsiveness, handling and drivability normally only encountered during abrupt emergency avoidance maneuvers or competition events.
On our test track in dry conditions all four tires delivered appropriate levels of traction and stability, but their overall handling and performance could be grouped into two pairs. The Continental and Michelin tires stood out from the other two tires in the test, both feeling stable and sure-footed when driven at the limit. The ContiProContact held a small advantage over the Primacy MXM4, using its additional ultimate cornering traction and quicker steering response to help it post the fastest lap time of the test. The Assurance ComforTred Touring trailed the Continental and Michelin tires by a small amount with some wheelspin during hard acceleration, and needing a larger steering input to hold a tight line around our constant-radius skidpad. The Turanza Serenity followed with predictable handling, but didn't have quite the ultimate grip to keep up with the leaders.
In the wet, the Primacy MXM4 was in a class by itself, thanks to plenty of cornering stability, braking traction and overall control as it lapped the track nearly one second faster than the next best tire. The ContiProContact followed with good overall grip, but a somewhat edgy feel as the limit was reached with less warning than the Michelin. The Assurance ComforTred Touring and Turanza Serenity both displayed less overall traction than the Michelin or Continental tires, feeling rather slippery and easily upset by abrupt inputs of the steering, throttle or application of the brakes.
Fuel Consumption Results
Our Real World Road Ride features a relatively flat 6.6-mile loop of 65 mph expressway, 55 mph state highway and 40 mph county roads along with two stop signs and one traffic light every lap. Our team drove approximately 500 miles over the course of several days. Since we wanted to compare fuel consumption results that typical drivers would experience, our drivers were instructed to maintain the flow of traffic by running at the posted speed limits and sustain the vehicle's speed using cruise control whenever possible. They did not use hypermiling techniques to influence vehicle fuel economy.
While none of the tires in this test were designed with low rolling resistance as a high-priority, we did find a difference in observed vehicle fuel economy. Based on our results the 1.4 mile per gallon difference between our lowest and highest observed fuel economy would result in an annual difference of about 27 gallons of premium gasoline. At the current cost of $2.75/gallon, it would amount to about $74 for drivers traveling 15,000 miles a year.
It's important to note our test's fuel consumption measurements follow consistent procedures designed to minimize variables that could influence the results, however they do not represent an exhaustive long-range fuel consumption study. While our procedures require the test vehicles in each convoy to run under the same prevailing conditions, the week-to-week differences in ambient temperatures, barometric pressures and wind speeds that we experience over a season of testing can influence vehicle fuel consumption and prevent the absolute mpg values of this test from being compared directly against those of others.
Larger differences in consumption between tires may indicate a difference that might be experienced on the road, while smaller differences should be considered equivalent. As they say, your mileage may vary.
Bridgestone Turanza Serenity (Grand Touring All-Season): Turanza with Serenity Technology tires are Bridgestone's Grand Touring All-Season tires developed for the drivers of sporty coupes and luxury performance sedans. Turanza with Serenity Technology tires are designed to provide Bridgestone's ultimate in ride and noise comfort while blending long wear with dry, wet and year-round traction, even in light snow. Read more.
Continental ContiProContact (Grand Touring All-Season): The ContiProContact is Continental's Grand Touring All-Season tire originally developed for European sport coupes and sedans sold in North America, and is now available for a wide range of imported and domestic cars. The ContiProContact is designed to blend good looks and handling with low noise and a smooth ride while providing all-season versatility and year-round traction, even in light snow. Read more.
Goodyear Assurance ComforTred Touring (Grand Touring All-Season): The Assurance ComforTred Touring is Goodyear's Grand Touring All-Season tire developed for the drivers of mid-range and upscale coupes, sedans and minivans. The Assurance ComforTred Touring was designed to combine looks, ride comfort and long wear with all-season traction, even in light snow. Read more.
Michelin Primacy MXM4 (Grand Touring All-Season): The Primacy MXM4 is Michelin's Grand Touring All-Season tire developed for luxury sedan and coupe drivers looking to combine all-weather handling and traction with good noise and ride comfort. Most Primacy MXM4 tires meet Michelin's Green X standard for low rolling resistance that confirms the tire's contribution to reducing vehicle fuel consumption and emissions of CO2 gases. The Primacy MXM4 is designed to blend a quiet, comfortable ride, responsive handling and enhanced fuel efficiency with year-round all-season traction, even in light snow. Read more.