1996 Cadillac Eldorado Owner's Manual - Page 300

Uniform Tire Quality Grading The following information relates to system the developed by the United States National Highway Traffic Safety Administration, which grades tires by treadwear, traction and temperature performance. (This applies only to vehicles sold in the United States.) The of grades are molded on the sidewallsmost passenger car tires. The Uniform Tire Quality Grading system does not apply todeep tread, winter-type snow tires, space-saver or temporary use spare tires, tires with nominal rim diameters of 10 to 12 inches (25 to30 cm), or to some limited-production tires. While the tires available on General Motors passenger cars and light trucks may vary with respect to these to grades, they must also conform Federal safety requirements and additional General Motors Tire Performance Criteria (TPC) standards. Treadwear The treadwear grade is a comparative rating based on the wear rateof the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear one and a half (1 1/2) timesas well on the government course as a tire graded 100. The relative performance of tires depends of upon the actual conditions their use, however, and may depart significantly fi-om the norm due to variations in driving habits, service practices and differences in road characteristics and climate. Traction -- A, B, C The traction grades, from highest to lowest, are B A, and C, and they represent the tire's ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces asphalt of and concrete. A tire marked C may have poor traction performance. Warning: The traction grade assigned to this tire based is on braking (straightahead) traction tests and does not include cornering (turning) traction. 6-41