Winnebago Towables User Manual page 24

SECTION 3 –
RECOMMENDATIONS
digit number, known as the aspect ratio, gives
the tire's ratio of height to width. Numbers of 70
or lower indicate a short sidewall for improved
steering response and better overall handling on
dry pavement.
R - The "R" stands for radial. Radial ply con-
struction of tires has been the industry standard
for the past 20 years.
Next number (Positions 8 and 9) - This two-
digit number is the wheel or rim diameter in
inches. If you change your wheel size, you will
have to purchase new tires to match the new
wheel diameter.
Next number (Position 10, 11 and/or 12) - This
two- or three-digit number is the tire's load
index. It is a measurement of how much weight
each tire can support. You may find this informa-
tion in your owner's manual. If not, contact a
local tire dealer.
Note: You may not find this information on all
tires because it is not required by law.
M+S - The "M+S" or "M/S" indicates the tire
has some mud/snow capability. Most radial tires
have these markings.
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 rat-
ings are listed below.
Note: You may not find this information on all
tires because it is not required by law.
3-10
Letter Rating
Q
R
S
T
U
H
V
W
Y
*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 -
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 the
tire was manufactured, and the last four numbers
represent the week and year the tire was built.
For example, the numbers 3197 means the 31st
week of 1997. The other numbers are marketing
codes used at the manufacturer's discretion. This
information is used to contact consumers if a tire
defect requires a recall.
Tire Ply Composition and Materials Used -
The number of plies indicates the number of lay-
ers 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 - Indicates the maxi-
mum load in kilograms and pounds that can be
carried by the tire.
Speed Rating
99 mph
106 mph
112 mph
118 mph
124 mph
130 mph
149 mph
168* mph
186* mph