Tire Tread Wear Marks And What To Look Out For To Avoid Tire-Related Crashes

Tire maintenance is a non-negotiable aspect of owning any vehicle. Well-maintained tires help people travel safely on the road, but neglected and poorly maintained ones spell trouble and accident.

The Fatality Analysis Reporting System or FARS in 2015 recorded 634 fatal tire-related motor vehicle crashes. This is why, before they fail, car owners should be responsible to inspect the tread wear marks regularly. The sheer volume of casualties from tire-related accidents on the roads already speaks a lot of the importance of keeping tabs of the tire’s tread wear marks.

Image source: commons.wikimedia.org

So, how should you maintain your tire? It’s simple. You should educate yourself in proper car maintenance and not rely so much on looking out for a house of tires in Reading, Pennsylvania (PA) for hours just to have somebody else figure everything out for you. You might have been looking out for tire places in North Reading, MA too. Or probably tire stores near Reading, MA (Massachusetts).  But knowing the basics of tire maintenance will teach you a lot and might help in keeping your family safe.

Every driver should learn reading tire sidewall codes. It is similar to reading tire sidewall information which explains a lot about your car’s tires. Here are the most important things you should learn about once you decide to drive a car:

  • How to read car tires sizes;
  • How to read numbers on tires like the load capacity and recommended air pressure;
  • Know about tires expiration and how to read it; and
  • Know when to buy new tires by the looks of the tread depth.

Being familiar with the basics of tire maintenance is crucial in order to avoid accidents brought by poorly-maintained tires.

How much tread is supposed to be on a tire?

Tread depth is the measurement between the top and the bottom of the tire’s rubber pattern. Monitoring your depth of tread is a good way to avoid an accident. You may measure the depth of tread with a gauge or the penny test. Neglecting the minimum required depth might cause you an accident. Make sure to assess your tire’s tread depth regularly. Here’s what you could use as a guide:

Tread depth Remarks
4/32” or deeper Good
3/32” Replace your tires soon
2/32” Replace your tires immediately

What are tired tread wear indicators?

Different tires used in different seasons have tread wear indicators or TWI’s. These indicators are usually found on newer tires. They appear as bars that are built into the tires. The bars would gradually appear as the tread wears down giving a warning to the car owner when it’s already time to replace the tires.

National Statistics on Tire-Related Crashes

Studies show that tire problems could affect the outcome of road accidents. Between 2005 and 2007, nine percent of almost 2.1 million vehicles that were involved in car crashes were reportedly caused by tire issues. The Insurance Institute for Highway Safety recorded 37,461 fatalities from motor vehicle crashes in 2016.

In the same year, 34,439 fatal motor vehicle crashes occurred. The table below presents the total tally of 11.6 deaths per 100,000 people in the United States and 1.16 deaths were recorded per 100 million miles traveled by motorists.

In Pennsylvania, there were 9.3 deaths recorded per 100,000 population and 1.16 deaths were recorded per 100 million miles a vehicle traveled. The figures are very close to the national statistics. Meanwhile, Massachusetts recorded a slightly lower figure of 5.7 deaths per 100,000 population and 0.66 deaths per 100 million miles traveled.

The same study found out that 563 drivers were killed in Pennsylvania due to car crashes, while 187 drivers were killed in Massachusetts. The total numbers of drivers killed in the United States that year reached 17,548.

Population, fatal motor vehicle crashes, motor vehicle crash deaths and motor vehicle crash death rates per state, 2016

State

Population Vehicle miles traveled (millions) Fatal crashes Deaths Deaths per 100,000 population

Deaths per 100 million vehicle miles traveled

Alabama

4,863,300 69,553 937 1,038 21.3 1.49
Alaska 741,894 5,030 78 84 11.3 1.67
Arizona 6,931,071 66,859 865 962 13.9 1.44
Arkansas 2,988,248 36,093 488 545 18.2 1.51
California 39,250,017 366,402 3,357 3,623 9.2 0.99
Colorado 5,540,545 52,993 558 608 11.0 1.15
Connecticut 3,576,452 31,987 281 293 8.2 0.92
Delaware 952,065 10,146 116 119 12.5 1.17
District of Columbia 681,170 3,553 26 27 4.0 0.76
Florida 20,612,439 220,083 2,933 3,174 15.4 1.44
Georgia 10,310,371 120,569 1,422 1,554 15.1 1.29
Hawaii 1,428,557 11,610 109 120 8.4 1.03
Idaho 1,683,140 17,677 232 253 15.0 1.43
Illinois 12,801,539 109,208 1,003 1,082 8.5 0.99
Indiana 6,633,053 83,322 768 821 12.4 0.99
Iowa 3,134,693 32,325 356 404 12.9 1.25
Kansas 2,907,289 32,122 381 429 14.8 1.34
Kentucky 4,436,974 49,491 763 834 18.8 1.69
Louisiana 4,681,666 49,468 704 757 16.2 1.53
Maine 1,331,479 14,979 151 161 12.1 1.07
Maryland 6,016,447 58,484 472 505 8.4 0.86
Massachusetts 6,811,779 59,004 359 389 5.7 0.66
Michigan 9,928,300 104,814 980 1,064 10.7 1.02
Minnesota 5,519,952 59,620 357 392 7.1 0.66
Mississippi 2,988,726 42,285 628 690 23.1 1.63
Missouri 6,093,000 75,713 868 945 15.5 1.25
Montana 1,042,520 13,181 171 190 18.2 1.44
Nebraska 1,907,116 20,818 194 218 11.4 1.05
Nevada 2,940,058 27,009 303 328 11.2 1.21
New Hampshire 1,334,795 13,510 130 136 10.2 1.01
New Jersey 8,944,469 76,941 569 601 6.7 0.78
New Mexico 2,081,015 26,348 358 402 19.3 1.53
New York 19,745,289 136,626 965 1,025 5.2 0.75
North Carolina 10,146,788 115,395 1,348 1,450 14.3 1.26
North Dakota 757,952 10,176 102 113 14.9 1.11
Ohio 11,614,373 119,046 1,053 1,132 9.7 0.95
Oklahoma 3,923,561 48,837 624 683 17.4 1.40
Oregon 4,093,465 37,492 446 495 12.1 1.32
Pennsylvania 12,784,227 102,775 1,088 1,188 9.3 1.16
Rhode Island 1,056,426 7,766 48 51 4.8 0.66
South Carolina 4,961,119 54,025 936 1,015 20.5 1.88
South Dakota 865,454 9,636 103 116 13.4 1.20
Tennessee 6,651,194 77,657 966 1,041 15.7 1.34
Texas 27,862,596 263,414 3,407 3,776 13.6 1.43
Utah 3,051,217 30,038 259 281 9.2 0.94
Vermont 624,594 7,325 57 62 9.9 0.85
Virginia 8,411,808 84,602 722 760 9.0 0.90
Washington 7,288,000 61,880 504 537 7.4 0.87
West Virginia 1,831,102 19,620 250 269 14.7 1.37
Wisconsin 5,778,708 63,575 544 607 10.5 0.95
Wyoming 585,501 9,595 100 112 19.1 1.17
U.S. total 323,127,513 3,220,677 34,439 37,461 11.6

1.16

Source: Insurance Institute For Highway Safety

How much tread is supposed to be on a tire?

Tread depth is the measurement between the top and the bottom of the tire’s rubber pattern. Monitoring your depth of tread is a good way to avoid an accident. You may measure the depth of tread with a gauge or the penny test. Neglecting the minimum required depth might cause you an accident.

Before you go to any house of tires in Reading, PA, and spend hours of figuring out what could be done to conduct a proper tire maintenance, familiarize yourself on how to assess your tire’s tread depth regularly. Here’s what you could use as a guide:

Tread depth

Remarks

4/32” or deeper

Good

3/32”

Replace your tires soon

2/32”

Replace your tires immediately

A study conducted by the National Highway Traffic Safety Administration (NHTSA) previously analyzed the crash-data from 2005 to 2007. The study found out that tire-related crashes are more likely to occur when the tire’s tread wear.

Tires with a full tread depth got 2.4 accident rate, while those with a tread depth of 0-2/32” got 26 percent accident rate.  Here are things to look out for when you are inspecting for tire tread wear marks:

Image source: kfz-betrieb.vogel.de
  • Inspect the depth of tread – You may check whether the depth of tread is still good or should be replaced right away through a penny test. Insert a Lincoln penny and when you see a large part of the coin is visible, the tread might already be about 2/32 inches. Remember that the depth of tread should never fall below 1/16 of an inch or 1.6 millimeters.
  • Check the tire for any cuts and bumps on the sidewall – Check the entire surface of the tire for any crack, cut, or bump.
  • Bead area damage –  The inner circle of the tire that connects the tire to the wheel and holds it together is called the bead area. If you see missing rubber parts or any damage on that area, your tire is unsafe to use.
  • Aging tire – Aside from knowing how to read tire tread wear marks, car owners should know how to read numbers on car tires. For instance, a driver should be familiar that there is such a thing as tires expiration and should know how to read it. The tire manufacturing date is shown in the last four numbers on the tire. The first two numbers indicate the week when the tire was made and the last two digits represent the year. For example, a tire with a DOT code of 1309 was made in the 13th week of 2009.
  • Excessive vibration while on the road – If you feel any irregular or excessive vibrations while you are driving, you may check out tire stores near Reading, MA or in Reading, PA depending on your location. Irregular vibrations are easy to spot as you feel sudden movements even when you are running on good road surfaces.

How Does Tire Pressure Affect Tread Wear?

Drivers should always check their car’s tire pressure to prevent uneven tire wearing and failure. The NHTSA’s study found out that underinflation of tires poses three times the risk of getting involved in a car crash. Underinflated tires of up to 25 percent are also prone to overheating that might lead to steering failure.  

The NHTSA’s study looked at the data during the time when tire-pressure monitoring systems weren’t required yet on all vehicles. It showed that five percent of all vehicles that were studied experienced tire problems immediately before a crash. Sixty-six percent of the vehicles are passenger cars, 17 percent are SUVs and the remaining are vans and pick-ups.

Can You Replace Your Tires With Used Tires?

You could replace your tires with used tires but there are certain conditions, although you  don’t have to know how to read tire tread wear marks because that job is reserved for experts. Unlike new tires, used tires near Reading, PA or used tires in Reading, MA, is not anymore subject to any legal standard or inspection process. It will come at a much cheaper price, however, used tires also have several disadvantages.

How To Read You Tire Sidewall

Tires manufactured after 2000 already have four-digit DOT code. The last two digits is the week and the next two is the year. But there is more to tires than it’s manufacturing date. Tire sidewalls also contain numbers and letters that tell you the following

Image source: rennwerks.com
  1. Type of the tire. Each type of tire comes with capacity and limitation. If the tire does not come with a letter, it could be a metric-sized tire. Here are various types of tire letter markings that indicate the service type.
  • P – The tire is for P-metric passenger vehicles. These include regular cars, SUVs, light-duty pickups with ¼-½ ton load capacities.
  • LT – The tire is for light trucks. These include some SUVs, medium and heavy-duty pickups with  ¾-1 ton load capacities.
  • ST – Stands for a special trailer tire used on utility, car, and boat trailers.
  • T – Also known as temporary (spare) tire which can be used until the repair or replacement of the main tire completed.
  • C – Euro-metric sizes with C indicates that the tire is for commercial use.
  • M – M indicates that the tire is for motorcycles. 

2. Width – The width is measured to show the distance from the inner sidewall to the outer sidewall. The tire’s first number shows the width in millimeters. The width varies depending on the rim.  

3. The height of its sidewall or the aspect ratio – After the width, the tire’s next two numbers on the sidewall will show the height of the sidewall in the percentage of the width. As the tire ratio increases so do the height and size of the sidewall. The aspect ratio determines the smoothness of the ride. Vehicles with higher tire aspect ratio provide smoother rides. 

4. Construction – Tire markings also indicate whether the tire is made via radial type or bias-belted and diagonal bias construction.

  • R – Radial tires, also called radial-ply tires, consist of layers of fabric like polyester and/or nylon plies that cover the circumference of the tires.
  • B – Belted-bias tires have belts made of steel and offers more support. These are preferred by those who own classic cars.
  • D – Diagonal bias tires have a series of tire plies layered diagonally. 

5. Size of the wheel where it fits – The number shows after the type of tire construction letter, indicates the size of the rim where it fits. Tires will only fit a wheel with its similar inner diameter.

6. Load capacity and speed rating – The load index and speed rating are displayed after the size of the wheel. Depending on the number written on the tire’s sidewall, you may use the guide for the load carrying capacity of the vehicle using the table below:

Load Index Pounds Kilograms Load Index Pounds Kilograms Load Index Pounds Kilograms
70 739 335 89 1279 580 108 2205 1000
71 761 345 90 1323 600 109 2271 1030
72 783 355 91 1356 615 110 2337 1060
73 805 365 92 1389 630 111 2403 1090
74 827 375 93 1433 650 112 2469 1120
75 853 387 94 1477 670 113 2535 1150
76 882 400 95 1521 690 114 2601 1180
77 908 412 96 1565 710 115 2679 1215
78 937 425 97 1609 730 116 2756 1250
79 963 437 98 1653 750 117 2833 1285
80 992 450 99 1709 775 118 2910 1320
81 1019 462 100 1764 800 119 2998 1360
82 1047 475 101 1819 825 120 3086 1400
83 1074 487 102 1874 850 121 3197 1450
84 1102 500 103 1929 875 122 3307 1500
85 1135 515 104 1984 900 123 3417 1550
86 1168 530 105 2039 925 124 3527 1600
87 1201 545 106 2094 950 125 3638 1650
88 1235 560 107 2149 975 126 3748 1700

(Table: Load Index Chart)

Rating Maximum Speed
Q 100 MPH
S 112 MPH
T 118 MPH
U 124 MPH
H 130 MPH
V 149 MPH
W 168 MPH
Y 186 MPH
Z Over 149 MPH

Meanwhile, the speed rating has a different chart and it shows an English alphabet letter that has a corresponding maximum speed that the tire can sustain when it is carrying the recommended load capacity.