Tiffin Motorhomes 2011 Phaeton, Руководство пользователя

Страница: 139 / 173

R O U T I N E M A I N T E N A N C E
14-19
Speed Rating —The speed rating denotes the speed at which a tire is designed to be driven for extended
periods of time. The ratings range from 99 miles per hour (mph) to 186 mph. These ratings are listed
below.
NOTE : You may not find this information on all tires because it is not required by law.
Letter Rating Speed Rating
Q 99 mph
R 106 mph
S 112 mph
T 118 mph
U 124 mph
H 130 mph
V 149 mph
W 168 * mph
Y 186 * mph
*For tires with a maximum speed capability over 149 mph, tire manufacturers sometimes use the letters
ZR. For those with a maximum speed capability over 186 mph, tire manufacturers always use the letters
ZR.
U.S. DOT Tire Identification Number —This begins with the letters “DOT” and indicated that the
tire meets all federal standards. The next two numbers or letters are the plant code where it was
manufactured, and the last four numbers represent the week and year the tire was built. For example, the
numbers 3197 means the 31
st
week of 1997. The other numbers are marketing codes used at the
manufacturer’s discretion. This information is used to contact customers if a tire defect requires a recall.
Tire Ply Composition and Materials Used —The number of plies indicates the number of layers of
rubber-coated fabric in the tire. In general, the greater the number of plies, the more weight a tire can
support. Tire manufacturers also must indicate the materials in the tire, which include steel, nylon,
polyester, and others.
Maximum Load Rating —This number indicates the maximum load in kilograms and pounds that can
be carried by the tire.
Maximum Permissible Inflation Pressure —This number is the greatest amount of air pressure that
should ever be put in the tire under normal driving conditions.