At Speedway Towing & Roadside Assistance, a great number of our roadside assistance calls are due to flat tires. Not only is it important to know about bolt patterns and rim diameter, you also need to know something about the tire itself. This will assist you in purchasing tire replacements too. Today we are going to consider the numbers marked on tires to help you better understand them.
Need for Tires
If you think about it, without tires America’s economy would literally grind to a halt. There are tires on cars, trucks, SUVs, vans, buses, heavy machinery; basically every type of rolling vehicle in the world. Even many toys have tires. Did you know that Lego is the largest tire manufacturer in the world? They produced 318 million plus back in 2011 alone! We ask a lot of our tires too. They need to deal with heat, shock and stress as well as road hazards such as glass and nails.
Tire Treadwear Rating – Uniform Tire Quality Grade (UTQG)
Tire treadwear is rated with a number and letters under the ‘Uniform Tire Quality Grade’ or the UTQG. The higher the number rating, the better the tire resists wear and the longer it lasts. The letter codes are the traction rating with AA being the highest and the temperature rating with A being the best. The temperature rating evaluates high speed performance, such as driving down highways on hot summer road surfaces without catastrophic failure. These treadwear ratings are highly technical with the tire manufacturers conducting their own testing according to standard test procedures. Treadwear ratings may offer relative information to the consumer when deciding on a tire purchase but consumer ratings and other information are an easier to understand rating of tire quality.
Parts of a Tire
The main part of a tire is the tread which is the outer circumference surface that makes contact with the road. Tire treads are made from elastomer copolymer with silica and carbon black usually added. The tread is molded over a nylon belt or crown over a steel mesh. Cords form the carcass ply and bead are the component keeping the tire together. The tire bead has a steel cable core with a low-flex ply wrapped around it and the bead is what holds the tire on the rim providing an airtight seal. In tubeless tires, a rubber liner holds in the air. The sidewalls are the flexible sides of the tire that support the crown and tread, and connect to the bead.
Types of Tires Explained
Construction types are radial, bias ply and bias-belted ply. Radials run the plies 90 degrees to the direction of travel, or ‘radially’ from the tires center to the other side. Bias tires run the ply at an angle relative to the tire center, with multiple ply layers running at an angle to each other. Because of this bias ply tires have a stiffer sidewall, as well as the tread and sidewalls being interdependent. In radial tires, the sidewalls are independent of the belt and tread. Bias ply tires offer lower rolling resistance than do non-belted tires. Radials on pavement outperform the bias ply tires offering the lowest rolling resistance, higher fuel mileage and a more comfortable ride. Off-road tires are generally steel belted radials with aggressive tread design.
Towing & Roadside Assistance & More in Irving, Fort Worth, Arlington, Carrollton & Plano Texas
Information including on the sidewall in addition to the UTQG rating are the tire size, load and speed ratings. Tire pressure recommendations in US and metric are also printed on the tire. DOT and International code compliance are listed, the manufacturer’s name, if snow rated a relative symbol is present and manufacture original equipment approval symbol. Lastly construction type and materials are listed. There is a lot to contemplate interpreting tire sidewall information. Take care of your vehicles shoes, for a long and safe ride. If however you do get a flat tire, call Speedway Towing & Roadside Assistance for a flat tire change to get you back on the road again quickly!