Mazda B4000 Owner's Manual page 231

7. H: Indicates the tire's speed rating. The speed rating denotes the
speed at which a tire is designed to be driven for extended periods
of time under a standard condition of load and inflation pressure.
The tires on your vehicle may operate at different conditions for load
and inflation pressure. These speed ratings may need to be adjusted
for the difference in conditions. The ratings range from 159 km/h (99
mph) to 299 km/h (186 mph). These ratings are listed in the
following chart.
Note: You may not find this information on all tires because it is not
required by federal law.
Letter rating
Q
R
S
T
U
H
V
W
Y
Note: For tires with a maximum speed capability over 240 km/h (149
mph), tire manufacturers sometimes use the letters ZR. For those with
a maximum speed capability over 299 km/h (186 mph), tire
manufacturers always use the letters ZR.
8. U.S. DOT Tire Identification Number (TIN): This begins with
the letters "DOT" and indicates that the tire meets all federal
standards. The next two numbers or letters are the plant code where
it was manufactured, the next two are the tire size code and the last
four numbers represent the week and year the tire was built. For
example, the numbers 317 mean the 31st week of 1997. After 2000
the numbers go to four digits. For example, 2501 means the 25th
week of 2001. The numbers in between are marketing codes used at
the manufacturer's discretion. This information is used to contact
customers if a tire defect requires a recall.
9. M+S or M/S: Mud and Snow. or
AT: All Terrain. or
AS: All Season.
Maintenance and Specifications
Speed rating - km/h (mph)
159 km/h (99 mph)
171 km/h (106 mph)
180 km/h (112 mph)
190 km/h (118 mph)
200 km/h (124 mph)
210 km/h (130 mph)
240 km/h (149 mph)
270 km/h (168 mph)
299 km/h (186 mph)
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