Over the White and Drifted Snow

All five brands of winter tires consistently outperformed the control set (Goodyear Eagle RS-A Plus) of all-season tires. The testing also showed that any set of four matched winter tires provided better performance than placing winter tires on the rear wheels only. Winter tires have specially designed tread patterns and are made of rubber compounds that deliver superior performance in cold weather or snow. The special tread designs include a large number of cuts or grooves in the tread block to increase control on wet surfaces and an open tread block pattern for better deep-snow traction. The testing was done on snow-covered test-driving tracks at the Royal Canadian Mounted Police Depot in Regina, Saskatchewan (Canada) in February 2004. Brands tested were the Continental ContiWinterContact TS790, Firestone Firehawk PVS, Goodyear Eagle Ultra Grip GW2, Michelin Pilot Alpin, and Pirelli Winter 210 Snowsport. The manufacturers submitted samples of commercially available, nonstudded winter tires sized for the rear-wheel-drive Ford Crown Victoria Police Interceptor. All of the tires tested were certified as meeting the North American Rubber Manufacturers' severe snow standard and were rated for police driving speeds. All the brands tested are designed for temperatures between -15 and -4 degrees Celsius (5 to 25 degrees Fahrenheit). During testing, temperatures were often lower. Each test run was performed on fresh snow. Data acquisition systems in the vehicles recorded time, distance, and acceleration. All winter tires were measured against a set of control all-season pursuit tires to help determine a baseline and evaluate whether temperature, wind, fresh snow, humidity, and sunshine conditions had changed.