Tires & Rims Information Center

How to choose tires and wheels for your car, van or SUV? What is the UTQG? Steel wheels or aluminium rims? This guide aims to answer some of your questions. See the topics below.

TIRE GUIDE	WHEEL GUIDE
The UTQG	Wheels
METRIC AND P-METRIC DIMENSIONS	Offset
RUNFLAT TIRE
Type of tire tread
Conventional sculpture tire

The P on the tire represents « passenger ». In some cases, you can find the inscription LT, which means light truck. You can also find the inscription T which means temporary. This tire is a spare tire only. It is important to note that this tire cannot be used normally like the other tires, or for a long period of time. On spare tires, there is a speed limit indicated. It is strictly recommended to avoid going to speed limit higher than the one indicated.

The (215) represents the width of the tire in millimetres from one sidewall to another.

The (65) represents the relation between the height and the width. Sometimes it is also called the tire profile which is represented in percentage.

The letter (R) represents the construction type of the tire.

The last group of numbers (15) represents the diameter of the rim in inches. However, you may sometimes find 17.5 inches rim. This type of rim is found on most vans or trucks with heavy charges. For example: 16.5, 19.5, 22.5, and 24.5.

The load rating is a numeric code that corresponds to the load capacity when the tire is inflated at its maximum. IMPORTANT: Never reduce the load rating lower than indicated by the constructor of the vehicle.

The speed rating is a letter which designs the precise mileage predefined by the constructors. IMPORTANT: Never change the speed rating required for a vehicle.

 

back to top

The UTQG

(UNIFORM TIRE QUALITY GRADE) holds three important notions: the tread ware index, the traction and the temperature. This information is differently enunciated according the each manufacturer. However, there are no laws involving these notions so it is important to compare different products inside a same manufacturer in order to use the information given.

 

The maximum cold air pressure is the maximum pressure that a tire can contain when it is cold, meaning when it has not been in action.

 

The D.O.T. (Dept of Transportation) is the tire series number. The first three letters represent the place when the tire was built. The three following letters represent the internal code for the fabricant. The first two numbers represent the fabrication week and the two last fabrication years.

 

On the winter tires, there are two indications missing compared to other tires. For example: There is the snowflake that is mandatory from December 15 to March 15 on winter tires in Quebec since the year 2008. This statement excludes the mention mud and snow, which means that a tire on which M+ S is indicated, is not necessarily designed and allowed for winter. There is also the indicator studless which means that the tire is non studdable. To stud tires, they must be new and never been on the road yet. Never install studs on tires that have been used on the road. Verify with your fabricant to know which crampon size to use. You should never use a different size than what is recommended. Crampons are part of the law regarding winter tires. These types of tires cannot be installed before October 15^th and must be removed before May 1^st.

 

The depth of the tread SE MESURE EN 32e DE POUCES***. This information is different from one tire to another and from one size to another. According to the law, a tire having 2/32e is no longer safe for driving on the roads. A tire 2/32e is extremely used, and in the industry it is recommended to change tires at 5/32e.

 

back to top

METRIC AND P-METRIC DIMENSIONS

 

back to top

RUNFLAT TIRE

 

This tire is designed to allow your vehicle to move for a certain distance, at a speed determined by the tire fabricant while it is flat. They are designed with reinforced resistant sidewalls that help support the mass of the vehicle when there is flat tire. It is even possible that you do not feel your tire being flat. It is necessary to use this type of tire with a tire pressing monitoring system (TPMS), which will warn you when there is air loss in the tire. Run flat tires are indicating by the following: SSR, DSST, ROF, RFT, RUNFLAT, ZERO PRESSION (ZP), and EMT.

IMPORTANT :

A run flat tire cannot be fixed. If you must replace a run flat tire on a vehicle, you must absolutely put back the same type of tire since that vehicle is not equipped with a spare tire. Aluminum wheels must be replaced by its original wheel. These wheels are found at the vehicle dealership and having a specific indication EH2.

 

back to top

Type of tire tread

Asymmetrical Tire

This concept combines two types of sculpture in order to offer adherence on dry or wet roads, allowing the tire to remain highly performing.  It has precise handling on wet roads without affecting the performance on a dry road. The part dedicated for humid surfaces is situated on the inside while it is located on the inside to have better road handling while turning on dry roads

back to top

Conventional sculpture tire

Characteristics and advantages:

The standard sculptures are disposed in a circumferential way around the tire in rows. It allows a quiet driving. The circumference furrows provide a good water storage/expulsion and allows the tire to move in both directions.

 

Tire maintenance

The tires, like the rest of the vehicle, demand certain maintenance. A tire that is badly maintained will use up prematurely and will not have as good road performance. To avoid premature usage of a tire there are many ways to prevent them.

 

1. Verify the air pressure when cold at least once a month. Refer to the air pressure recommended by the constructor of the vehicle that will be indicated either on the door of the vehicle or in the owner’s manual. Putting nitrogen in your tires instead of normal air will not demand often verification because this gas is more stable. 

 

1. The interchange of the tires is very important for a long lasting tire life time. With rotations at every recommended kilometre by the manufacturer, the durability of the tire will increase by approximately 20%.

 

1. Vehicle alignment is strongly recommended twice a year. For example, when you change your tires for the season, you should verify the alignment at the same time. A vehicle that is correctly aligned will reduce the risk of premature usage and a better control of the vehicle.

 

1. As for the cleaning of the tires and wheels, you can wash them with water and soap with a gentle cloth. However, do not use the product Armor all because the tire will crack and dry up in the sun.

 

1. If you must change two tires on a vehicle that have the same size on all four wheels, you must keep the same speed rating, the same load rating, as well as the same tread design. New tires should be mounted at the back of the vehicle. This applies to all vehicles regardless of their driving axle (front traction or propulsion). Don’t forget that you must change all four tires on a four wheel drive vehicle.

 

If you must match tires, you must keep the load rating and the speed rating identical to the two other tires that will remain on the vehicle. You must also keep the same tread. For example, if the two remaining tires on the vehicle are directional, then the two new tires must also be directional. In some cases, matching tires is not recommended. Ideally, try to match tires with the same brands

The steel wheel is found on most basic vehicles and certain vans. Sometimes, certain clients will use steel wheels during winter, but they will use aluminum wheels in the summer.

The tires, like the rest of the vehicle, demand certain maintenance. A tire that is badly maintained will use up prematurely and will not have as good road performance. To avoid premature usage of a tire there are many ways to prevent them.

 

1. Verify the air pressure when cold at least once a month. Refer to the air pressure recommended by the constructor of the vehicle that will be indicated either on the door of the vehicle or in the owner’s manual. Putting nitrogen in your tires instead of normal air will not demand often verification because this gas is more stable. 

 

1. The interchange of the tires is very important for a long lasting tire life time. With rotations at every recommended kilometre by the manufacturer, the durability of the tire will increase by approximately 20%.

 

1. Vehicle alignment is strongly recommended twice a year. For example, when you change your tires for the season, you should verify the alignment at the same time. A vehicle that is correctly aligned will reduce the risk of premature usage and a better control of the vehicle.

 

1. As for the cleaning of the tires and wheels, you can wash them with water and soap with a gentle cloth. However, do not use the productArmor all because the tire will crack and dry up in the sun.

 

1. If you must change two tires on a vehicle that have the same size on all four wheels, you must keep the same speed rating, the same load rating, as well as the same tread design. New tires should be mounted at the back of the vehicle. This applies to all vehicles regardless of their driving axle (front traction or propulsion). Don’t forget that you must change all four tires on a four wheel drive vehicle.

 

If you must match tires, you must keep the load rating and the speed rating identical to the two other tires that will remain on the vehicle. You must also keep the same tread. For example, if the two remaining tires on the vehicle are directional, then the two new tires must also be directional. In some cases, matching tires is not recommended. Ideally, try to match tires with the same brands.

 

back to top

Wheels

Two types of wheels exist: steel wheels and aluminum rims. These two wheels are completely different from one another and have very different functions.

The aluminum wheel is very light. This wheel is also known as mag. It is also found on most vehicles and certain vans. This type of wheel is usually nicer on the eyes. It provides on certain vehicles better performance and a more rapid cooling breaking system, as well as better reaction from suspension.

back to top

Offset

The rim diameter is measured from the interior corner of tire heel.

The rim width is the distance measured between the corners of the tire bead seats.

The bolt pattern diameter is the diameter which joins the center of the bolt holes.

In the cases of the aluminum wheels you must always center the mag with the hub and never only the bolts.

The offset is the distance measured between the central axis of the tire and the surface of the wheel. There are three types of offset: the positive offset, the neutral offset, and the negative offset.