Tire load index

Tire Load Index - a conventional numerical designation that shows what mass load the tire can withstand in long-term operation. This information is necessary in order to choose the right tires, and thereby ensure a safe and comfortable ride. To decipher the tire load index, a table is used, which shows the numerical designations of the index and the normal values ​​\uXNUMXb\uXNUMXbof the mass that corresponds to them.

Load value (MAX LOAD) and tire pressure

further we will give you such a table, as well as give information about speed index, which is also important when choosing a tire. You can read the rest of the information about the designations available on the tires in addition.

Determination of the load index

First of all, you need to remember that the numerical values ​​\uXNUMXb\uXNUMXbof the load index given on the tires are conditional! That is, these numbers do not mean the absolute maximum weight for which the tire is designed. As the load index increases, the maximum allowable weight of the vehicle for which it is designed also increases.

However, in terms of application, many drivers are interested in a simple question when buying new tires - which tire load index to choose in one case or another? It is easy to answer it. There are two options. The first is to ask for relevant information in the manual for your car or in the reference literature. Many automakers directly indicate the information that a particular model needs a tire with such and such a load index (the same applies to the speed index, although selection is easier there, but more on that later). The second option is to do the calculations yourself.

Load index for passenger cars can be calculated based on the unladen weight of the vehicle with the maximum load. That is, to the mass of an equipped vehicle (with a fully filled fuel tank, process fluids, a repair kit, a spare wheel, and so on), the mass of the maximum number of people placed in it is added (for cars usually it is 5), as well as some mass of additional cargo (it all depends on the specific car, for small cars it can be 100 ... 200 kg, and for SUVs - over 500 kg). Approximate value of indices for different types of cars:

• 60 - load up to 250 kg - for A-class cars;
• 68 - up to 315 kg per wheel - for B-class representatives;
• 75 - 387 kg per wheel - for C-class cars;
• 87 - 545 kg load - for minivans and crossovers;
• 99 - 775 kg - for SUVs and light commercial vehicles.

then the resulting maximum mass must be divided by four (for traditional machines with four wheels). And after that add 35…40% of the stock. Having carried out such simple calculations, you will get the absolute value in kilograms that the tire must withstand. The final stage is the choice of a symbol for the vehicle load index according to the table. Please note that you need to select the coefficient corresponding to the nearest HIGHEST absolute value..

in order not to bother with the calculations of the load index required for the tires of your car, it is possible to quickly calculate everything on a special calculator. It will immediately give you the right number.

Often, for specific models of cars in stores, there are already several options, from which you can choose the most suitable for you in terms of quality, price and manufacturer.

Actual to produce stock for rear wheelsespecially if you often carry heavy loads. However, do not be zealous and make a choice of tires with an index that is too high. The fact is that the more load the tire is designed for, the more rubber is used for its manufacture. Accordingly, such a tire will be heavier, and from here appears three negative factors.

The first is that the internal combustion engine will be forced to spend additional efforts (and hence fuel!), In order to rotate the heavy wheel. The second is that a heavy tire will be very stiff, so it will be uncomfortable to ride on it. The third - with heavy tires, the car's suspension experiences an additional load, which means that its normal operation period is reduced.

then we give you the promised table that will help you decipher the tire load index (here you will find tire values ​​\u60b\u125bfor all types of cars - cars, SUVs, trucks, and so on). For cars and SUVs, tires with an index value from XNUMX to XNUMX are used (respectively, from “A” class cars to heavy SUVs).

Load index	Maximum weight, kg	Load index	Maximum weight, kg
0	45	100	800
1	46,2	101	825
2	47,5	102	850
3	48,7	103	875
4	50	104	900
5	51,5	105	925
6	53	106	950
7	54,5	107	975
8	56	108	1000
9	58	109	1030
10	60	110	1060
11	61,5	111	1090
12	63	112	1120
13	65	113	1150
14	67	114	1180
15	69	115	1215
16	71	116	1250
17	73	117	1285
18	75	118	1320
19	77,5	119	1360
20	80	120	1400
21	82,5	121	1450
22	85	122	1500
23	87,5	123	1550
24	90	124	1600
25	92,5	125	1650
26	95	126	1700
27	97	127	1750
28	100	128	1800
29	103	129	1850
30	106	130	1900
31	109	131	1950
32	112	132	2000
33	115	133	2060
34	118	134	2120
35	121	135	2180
36	125	136	2240
37	128	137	2300
38	132	138	2360
39	136	139	2430
40	140	140	2500
41	145	141	2575
42	150	142	2650
43	155	143	2725
44	160	144	2800
45	165	145	2900
46	170	146	3000
47	175	147	3075
48	180	148	3150
49	185	149	3250
50	190	150	3350
51	195	151	3450
52	200	152	3550
53	206	153	3650
54	212	154	3750
55	218	155	3875
56	224	156	4000
57	230	157	4125
58	236	158	4250
59	243	159	4375
60	250	160	4500
61	257	161	4625
62	265	162	4750
63	272	163	4875
64	280	164	5000
65	290	165	5150
66	300	166	5300
67	307	167	5450
68	315	168	5600
69	325	169	5800
70	335	170	6000
71	345	171	6150
72	355	172	6300
73	365	173	6500
74	375	174	6700
75	387	175	6900
76	400	176	7100
77	412	177	7300
78	425	178	7500
79	437	179	7750
80	450	180	8000
81	462	181	8250
82	475	182	8500
83	487	183	8750
84	500	184	9000
85	515	185	9250
86	530	186	9500
87	545	187	9750
88	560	188	10000
89	580	189	10300
90	600	190	10600
91	615	191	10900
92	630	192	11200
93	650	193	11500
94	670	194	11800
95	690	195	12150
96	710	196	12500
97	730	197	12850
98	750	198	13200
99	775	199	13600

Speed ​​index

The designations of the load index and tire speed on the lateral surface of the rubber are located nearby. And this is no accident, because they are interconnected. Unlike the load, the speed index has a letter designation in Latin letters (from A to Z). For example, you can find the values ​​92S or 88T on the tire, which will just be the joint designation of the two mentioned indices.

The speed index is specially placed next to the load index. This information gives an idea. what kind of load can the tire withstand at its maximum speed.

Deciphering the tire speed index is very simple. The closer the letter is to the end of the alphabet, the more speed the tire is designed for. The only exception is the letter H, located between U and V. So, we give you a similar table with which you can clarify what maximum speed this or that tire is designed for.

Speed ​​index	Maximum speed km / h
A	40
B	50
C	60
D	65
E	70
F	80
G	90
J	100
K	110
L	120
M	130
N	140
P	150
Q	160
R	170
S	180
T	190
U	200
H	210
V	240
W	270
Y	300
VR	> 210
ZR	> 240
(W)	> 270
Z	> 300

How to choose load and speed indices

Deciphering load and speed indices

European regulations ECE-R54 require all tire manufacturers to put load and speed index values ​​on them. In this case, the load index is usually indicated for single installation wheels on an axle on one side. If the rubber can be used for a double installation, then two values ​​\u102b\u100bare indicated through a dash. For example, XNUMX/XNUMXR. The first number is for a single installation, the second is for a dual installation. Tires have such a double designation Commercial class, which, in accordance with the same rules, can be installed not only on cars, but also on small trucks and vans (that is, commercial vehicles). Such tires are additionally indicated by the letter C or the word Commercial.

It is impossible to install tires with load and speed indices lower than those prescribed in the documentation.

As for the speed index, it does not only affect the maximum allowable speed for which the tire is designed. The fact is that you can’t drive for a long time (more than half an hour) at this very maximum speed. This is due to excessive tire wear. In addition, it is life-threatening, because at high speeds the rubber should work in normal, not critical modes. Therefore, it is allowed to drive for a long time at speeds 10 ... 15% lower than the maximum allowable. Such reasoning is especially relevant for bad roads, when the rubber constantly gets into pits, potholes and runs into bumps.

Do not exceed the speed limit and do not drive for a long time at the maximum speeds allowed for rubber.

When choosing tires by speed index, as in the case of a load, you cannot choose very “fast” tires. The fact is that the faster the tire is designed for, the softer it is. Accordingly, it will have better and more reliable grip on the road surface. However, such rubber is much wears out faster (remember how often tires are changed at Formula 1 races). That is why it is not recommended to buy very high-speed tires for ordinary cars used in urban areas.

Results

We are sure that the above information will help you understand what the load and speed indices of tires mean, whose designations are located behind the tire size value. This will help you make the correct selection. At the same time, do not forget to leave a small margin of 10 ... 20% for both indices in order to ensure driving comfort and safety on the road.