Merritt GOOSENECK LIVESTOCK TRAILER, Owner'S Manual

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WHEELS AND TIRES
8-5
Next number
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
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 information 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 that the tire has some mud
and snow capability. Most radial tires have these
markings; hence, they have some mud and snow
capability.
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.
•
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
indicates 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 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 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.
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