Tires come in a wide variety of sizes, treads, and ratings. Therefore, understanding tire specifications is critical to getting the right tires for your car.
For example, you might ask yourself, “What does 116T mean on a tire?” This article answers that question and many others so you can figure out tire ratings.
Tire Load Index and Speed Classification System Explained
The tire load index and speed rating system help communicate tire designs. The load index specifies how much weight the tire can handle, while the speed rating tells us how fast the tires can go.
For example, if you ask yourself, “What does 116T mean on a tire?” means the load index is 116 and it can handle 2,756 pounds, while the T indicates a speed rating of 118 mph.
The load index is a numerical value. The higher the number, the more weight the tire can handle. Here is a summary table of the charge index, but there are also classifications between these index numbers:
Load Index Load (lbs)
0 99
5 114
10 132
15 152
20 176
25 204
30 234
35 267
40 309
45 364
50 419
55 481
60 551
sixty five 639
70 739
75 852
80 992
85 1135
90 1323
95 1521
100 1764
105 2039
110 2337
115 2679
120 3086
125 3638
130 4189
135 4806
140 5512
145 6393
150 7385
The speed rating is usually a numerical symbol, but can also include letters. For example, here is a speed index list with the top speeds that correspond to each index rating:
Symbol Speed (mph)
A1 3
A2 6
A3 9
A4 12
A5 16
A6 19
A8 25
B31
C 37
D 40
my 43
F50
GRAM 56
j 62
k68
L 75
SUBWAY 81
north 87
PAGE 94
q 100
R 106
S 112
T118
you 124
h 130
V 149
W 168
and 186
What does the T or H mean on the tires?
The letters that are part of the speed rating provide a specific speed at which the tires are safe to use. This rating does not mean that the speeds are safe for the roads or legally permitted, but only specifies the maximum speed.
If you see a T in the tire speed rating, that means the tire can go up to 118 mph. There aren’t many roads where it’s legal to go that fast, but if you can find the right spot, tires with a T speed rating can go up to 118 mph.
H speed rated tires can go extremely fast. The H-rated tire maker made them handle speeds of 130 mph. But just because your tires can go so fast, your car may not be able to.
Generally speaking, the closer the rating is to the beginning of the alphabet, the lower the speed rating will be. The speed rating increases as you get to the end of the alphabet.
What does a charge index of 116 mean?
The load index is a rating of how much weight each tire can carry. Load index is per tire. So if your car has four tires, you can multiply the load index by four to get the total weight the tires can safely handle.
If you see a load index of 116, that means each tire can handle 2,756 pounds. So the total load of a car with four tires is about 11,024 pounds.
It is worth noting that most vehicles do not have an even distribution of weight. This fact is especially true if you are placing heavy loads on an axle, which is often the case with large trucks and vans.
What do the other numbers and letters on a tire mean?
If you inspect a tire, you will find many numbers and letters next to speed and load ratings. One of the most important is a combination of three numbers that indicates the size and shape of the tire.
An example is a 275/70R17 tire size. In this case, the 275 stands for the width of the tire in millimeters, the 70 stands for the aspect ratio, and the 17 stands for the size of the wheel’s rim. The R indicates that the tire uses a radial construction.
Another critical number found on tires is the cold PSI rating. This rating is the maximum tire pressure that is safe to use for the tire. You want to follow the manufacturer’s recommended tire pressure, which is often listed on a label near the driver’s seat, door, or door jamb.
R16
If you see R16 on a tire, the R means it has a radial construction, a common tire construction. The 16 indicates the wheel size, and these tires will fit wheels that measure 16 inches in diameter.
245
If you see 245 as the first number in the three number series, the tires are 245mm wide. So if you were to remove the tire from your car and place it on a flat surface, the tread would stick out 245mm into the air.
245/70
Let’s continue with the same example of 245 and add the next number which shows 70. This number is a hard measurement to visualize, but it is the aspect ratio of the tires, calculated by dividing the tire height from the rim by the width.
A number of 70 indicates that the height of the tire is 70% of its width.
245/70R19
If we include the last part of the tire size, it will identify the size of the rim. In this example, the tire fits a 19-inch diameter rim. In short, it’s a 245mm wide tire with 70% aspect ratio and sits on a 19-inch rim.
116t
This rating will be separate from the tire size, and because it is a number combined with a single letter, it is the speed and load rating of the tire. So, for example, 116 is the load rating for 2,756 pounds and t is the speed rating for up to 118 mph.
What happens if you exceed the load and speed ratings of the tires?
Tires are a critical part of any vehicle. If they fail, catastrophic problems can occur. You must use the tires for their intended use, which means they must be the correct size, filled with the correct tire pressure, and at the correct load and speed.
What happens if you exceed the load and speed ratings of the tires? You are pushing your luck and it could cause the tire to fail. Extra weight or speed can put more pressure on the tire than it was designed for, which could cause it to break down quickly.
