1997 Honda Odyssey Owner's Manual - Page 220

Tire Information Tire Pressure Adjustment For High Speed Driving Honda strongly recommends that you not drive faster than posted speed limits and conditions allow. If you decide it is safe to drive at high speeds, be sure to adjust the cold tire pressures as shown below. If you do not adjust the tire pressure, excessive heat can build up and cause sudden tire failure. Be sure to readjust the pressure for normal driving speeds. You should wait until the tires are cold before adjusting the tire pressure (see page 171). DOT Tire Quality Grading (U.S. Cars) The tires on your car meet all U.S. Federal Safety Requirements. All tires are also graded for treadwear, traction, and temperature performance according to Department of Transportation (DOT) standards. The following explains these gradings. Treadwear The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear one and one half (1-1/2) times as well on the government course as a tire graded 100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices and differences in road characteristics and climate. CONTINUED Technical Information