Bursting Tires Frequently? Learn How to Read Tire Sidewalls

This information, relating to tire grip, handling, load, speed index, etc is largely ignored by vehicle owners – once the tire fits (and in places where winters can be extreme, whether or not it falls in tune with the season).

Unfortunately, this is the major cause of burst tires, especially on the freeways. If you’ve burst a tire before (as shown in the photo below). great chances are that you missed the very important information on the sidewall – or failed to interpret it correctly.

Today, I’ll be offering a helping hand and taking you across the various inscriptions on the tire sidewall and what they mean.

Follow me down the page; let’s get down to business!

Reading a Tire Starts and Ends with the Tire Sidewall

Unlike general goods found in the open market, the tire of an automobile doesn’t have its critical info on its packaging (some tires don’t even come packaged at all).

Instead, what you get is ALL the critical information, embossed clearly on the tire’s sidewall.

Because of how important this is, there isn’t any bothering about lost packaging or worse, faded-out printing. This is why, this is beautifully embossed (even on the cheapest tires) and not printed.

The sidewall remains the most authoritative source of vehicle tire information: not the manufacturer’s website, not the labeling (if any), but the good old sidewall.

So, what do the letters, numbers, and combinations on the tire sidewall mean?

Meaning of the Numbers on the Tire Sidewall

An automobile tire will have numbers, letters, and a combination of both, clearly embossed on its sidewall.

This is what they mean:

1. The Tire Size

If you’re interested in reading a tire, this is where it starts. A vehicle tire size will usually be written as an expression of tire width, the aspect ratio, and the diameter of the wheel (the first two being expressed in millimeters while the latter being expressed in inches).

For instance, take a vehicle with a tire size of 215/55R17.

What this translates to is:

• “215” millimeters is the width of the tire.
• “55” represents the aspect ratio (which is a product of the sidewall height as a percentage of the width). The higher this figure, the more visible ‘sidewall material’ is seen. The lower the figure goes, the lesser ‘sidewall material’ is seen.
• “R” simply indicates that the tire is constructed in a redial fashion (as opposed to the older, almost forgotten, bias ply design).
• Finally, the “17” means the tire is designed to be fitted onto a 17-inch wheel (diameter-wise).

2. Tire Production Date

In the process of reading a tire, the production date is very important – right next after the tire size.

This is why: rubber, the primary raw material for the production of automobile tires is only good for some years, as a finished product before it becomes brittle, hardened, cracks, or winds up being generally unsafe.

To be on the safe side, tire manufacturers always emboss (not print) the month and year of manufacture of a tire, right on its sidewall.

For premium tires like Michelin, they’re good for ten (10) years, post-production – after which, it only makes sense to change them.

For budget tires, five (5) years is about the upper mark (though three appears to be the sweet spot from experience).

For example, if you come across some badging on a tire that reads 06/25, it simply means that the tire was produced in the 6th week of 2025 – which essentially means the tire rolled off the assembly line in the second week of February 2025.

Now, depending on local laws (and the inherent quality of the tire itself, as suggested by its manufacturer), you’ll have a fair idea as to when to change it/them.

3. Temperature Rating

The temperature rating of a tire determines its speed durability. Here, a higher rating indicates that the tire can withstand and dissipate heat better than a similar (but lower-rated unit).

Based on the Uniform Tire Quality Grading System (UTQG), developed by the National Highway Traffic Safety Administration, an arm of the US Department of Transportation,

Together with traction and tread depth, the temperature rating of a tire positively points to the performance of such a tire on the road, especially when conditions of use are severely adverse.

Determined in a laboratory on an indoor test wheel, the test involves inflating the tire and spinning it against a high-speed drum. The resulting rating, A, B, or C indicates safe performance at speeds above 115, 100-115, and 85-100 mph, respectively.

This rating appears on the sidewall of the tire as: Temperature: ‘A’ (or ‘B’ or ‘C’).

If you pay special attention to this rating before buying (or using) any tire, you’re guaranteed to get a tire that will serve you faithfully for years to come (provided you use it in the manner specified).

4. Traction

While not directly related to bursting tires because you failed to read the sidewall information, the traction rating of a tire indicates how well such a tire can stop on wet pavement (or in slippery conditions, generally).

Rated from “AA” through to “C”, a tire rated “AA” will have the highest stopping power on wet road conditions, a tire rated “A” will offer good, grip, “B” will offer acceptable grip while “C” will offer poor grip, when the conditions get wet.

If you drive where it rains (or snows) all the time, your best bet is to opt for a make and model of tire with the best wet traction possible, “AA”.

The traction rating of a tire is usually displayed on the sidewall of that tire, along with the temperature and treadwear ratings.

5. Treadwear Rating

You cannot explain tire codes without mentioning a very important rating that many tire buyers don’t even bother with, almost all the time: the treadwear rating.

Running from 100 through to 1000, a tire’s treadwear rating indicates how long the tread is expected to last. Here, a ‘standard’ control tire is assigned a rating of 100, and other tires leaving the factory are tested against the standard control tire, with a rating of 200, for example, expected to last twice as long as the control tire.

The higher the treadwear rating, the better (as the tire will last longer before needing to be replaced, all other things being equal).

Since tire treads are essentially what helps with grip (and stopping), it makes perfect sense to read this sidewall tire information carefully to avoid road mishaps (at the worst) or buying tires in an unplanned manner (at the best).

6. Intended Use (Weather Wise)

There are generally three (3) types of tires, classified by their intended use, weather-wise. These are: winter, summer, and all-season tires.

Winter tires are specifically designed to perform in snow and wet conditions including ice, snow, and slush. Made with a rubber compound that stays soft in extreme cold, these tires degrade/wear out rapidly in summer and should only be used during periods of extreme cold. They are marked with the 3PMSF (3-Peak Mountain Snowflake) symbol and occasionally, have also have the wording, M+S (mud + Snow) accompanying or as standalone. However, this isn’t a conclusive indication that a tire is designed for and will perform awesomely in snow.

Summer tires are designed to perform well in warm weather and as a natural consequence, struggle in winter and are likely to leave you trapped and stranded (when used during winters). These tires are made of large tread blocks that grip the road in dry and moderately (rainy) wet conditions, making them ideal for performance. The sidewalls of these tires have no marking on their own and the 3PMSF together with the ‘M+S’ sign are all conspicuously absent on the sidewall of the tire.

Finally, there are the all-season tires, designed to handle both summers and winters to an extent. These tires are marked with an ‘M+S’ and work fairly well in both temperature extremes, especially if you’re only just getting to it.

7. Load Rating

The load index indicates how much weight a vehicle tire can handle when inflated to its maximum (safe) pressure. The numbers here range from 70 to 126 and are usually multiplied by four (the number of tires on most vehicles) and compared against a vehicle’s gross weight.

Here’s the summary:

Load Index	Load (lbs)	Load Index	Load (lbs)	Load Index	Load (lbs)
0	99	50	419	100	1764
1	102	51	430	101	1819
2	105	52	441	102	1874
3	107	53	454	103	1929
4	110	54	467	104	1984
5	114	55	481	105	2039
6	117	56	494	106	2094
7	120	57	507	107	2149
8	123	58	520	108	2205
9	128	59	536	109	2271
10	132	60	551	110	2337
11	136	61	567	111	2403
12	139	62	584	112	2469
13	143	63	600	113	2535
14	148	64	617	114	2601
15	152	65	639	115	2679
16	157	66	639	116	2756
17	161	67	677	117	2833
18	165	68	694	118	2910
19	171	69	716	119	2998
20	176	70	739	120	3086
21	182	71	761	121	3197
22	187	72	783	122	3307
23	193	73	805	123	3417
24	198	74	827	124	3527
25	204	75	852	125	3638
26	209	76	882	126	3748
27	215	77	908	127	3858
28	220	78	937	128	3968
29	227	79	963	129	4079
30	234	80	992	130	4189
31	240	81	1019	131	4289
32	247	82	1047	132	4409
33	254	83	1074	133	4541
34	260	84	1102	134	4674
35	267	85	1135	135	4806
36	276	86	1168	136	4938
37	282	87	1201	137	5071
38	291	88	1235	138	5203
39	300	89	1279	139	5357
40	309	90	1323	140	5512
41	320	91	1356	141	5677
42	331	92	1389	142	5842
43	342	93	1433	143	6008
44	353	94	1477	144	6173
45	364	95	1521	145	6393
46	375	96	1565	146	6614
47	386	97	1609	147	6779
48	397	98	1653	148	6844
49	408	99	1709	149	7165
				150	7385

With this clearly indicated on the sidewall of the tire you intend to buy, you know exactly if a tire will serve your vehicle or not (even if it fits, physically).

8. Speed Rating

The speed rating of a vehicle tire is the tire’s maximum (safe) speed capability. Usually the last character after the load index, it spans from A1 right through Y.

Here’s the summary:

Speed Rating Symbol	Speed (mph)	Speed (km/h)
A1-A8	<25 mph	<40 km/h
B	31 mph	50 km/h
C	37 mph	60 km/h
D	40 mph	65 km/h
E	43 mph	70 km/h
F	50 mph	80 km/h
G	56 mph	90 km/h
J	62 mph	100 km/h
K	68 mph	110 km/h
L	75 mph	120 km/h
M	81 mph	130 km/h
N	87 mph	140 km/h
P	94 mph	150 km/h
Q	100 mph	160 km/h
R	106 mph	170 km/h
S	112 mph	180 km/h
T	118 mph	190 km/h
U	124 mph	200 km/h
H	130 mph	210 km/h
V	149 mph	240 km/h
ZR	Above 168 mph	Above 270 km/h
W	168 mph	270 km/h
Y	186 mph	300 km/h
(Y)	Above 186 mph	Above 300 km/h

From the above, a tire-rated ‘V’ (for instance) can safely travel up to 149 mph (240 km/h), assuming the load rating is right.

Other Miscellaneous Tire Sidewall Information

Reading a tire doesn’t usually go beyond what has been shared above here. However, paying attention to the below miscellaneous points will also provide an added measure of peace of mine when on the road.

1. Country of Manufacture

The country of manufacture of a tire doesn’t generally matter. However, tires made in North America and Europe, generally, are made to a higher standard than those made elsewhere (largely because of the stringent quality quality of these places).

2. Direction of Travel

It may surprise you to know that some tires have a direction of travel that they are meant to follow. Unfortunately, this info on the tire sidewall is most times ignored by tire fitting folks, which with other issues, is likely to end up in a manner one did not plan.

3. Fitting Instruction(s)

Finally, in reading a tire, the fitting instruction(s) are there for a reason: they aren’t mere advice or suggestions. If the manufacturer indicates that a certain side of the tire should be fitted outside, it’s best to make sure that the side remains outside, all the time.

How an Understanding of These Sidewall Information Helps

Tires are the most important thing on a vehicle, safety-wise. They are what make contact with the road. At certain speeds, a challenge with any tire easily spells doom – even if you don’t know or understand this part of tires.

This is why, carefully reading the information on a tire sidewall and adhering to what it says regarding a tire’s suitability for your vehicle isn’t advisory: it remains counsel that must be taken, at the pain of physical injury (or mechanical damage) if ignored.

If you take your tire sidewall seriously, your vehicle is likely also not to disappoint you, irrespective of the challenges you throw at it, all year round.

Summary

The meaning of numbers on the tire sidewall is as varied as they’re comprehensive. The entry above has seen to this – and adequately done justice to same.

Making up 11 components (both major and minor), keeping a vehicle safe while speeding to its destination doesn’t get more complex than the tire.

Make certain that you take special note of the:

1. Tire size.
2. Production date.
3. Temperature rating.
4. Traction.
5. Treadwear rating.
6. Intended use.
7. Load rating.
8. Speed rating.
9. Country of manufacture.
10. Direction of travel.
11. Fitting instructions.

And you’ll be alright, all the time.

Reference

1. 2015 Consumer Guide to Uniform Tire Quality Grading (PDF).

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