Rims Buying Guide

Rim Sizes | Winter Rims | Wheel Installation | Technical | Maintenance

Rim Sizes

Plus Sizing

Plus sizing involves replacing your vehicle's original tires and rims wheels with a wider tire and a larger diameter rim. Not only does this improve your vehicle's stability and handling by putting more rubber on the road, it also gives your vehicle a distinctive look of performance.

When plus sizing, it is key to ensure the total diameter of your tire and rim remains the same as your original tires. A variance of more than 3% from your original equipment can cause problems with transmission shift points, which can decrease fuel mileage. It can also confuse braking system computers, which can even lead to brake failure.

With a wider rim, you will need a lower-profile tire (ie., a tire with a shallower sidewall).
Low profile tires don't have as much "give" along the sidewall, which results in a rougher ride—you are trading comfort for performance.

Tire Plus Sizing

Here's the rule of thumb for "plus sizing":

Plus 1 Sizing	Plus 2 Sizing
Increase tire section width by 10 mm	Increase tire section width by 20 mm
Decrease tire aspect ratio by 10 points	Decrease tire aspect ratio by 20 points
Increase rim diameter by 1 inch	Increase rim diameter by 2 inches

This approach is not exact, but it will generally get you in the right ballpark. Consult with the experts in the Canadian Tire Auto Service centre when you are purchasing rims and tires to ensure you will get a proper fit.

Rim Diameter/Width

You can easily find out the rim size that is required for your vehicle by looking at the side of your tire. On the tire wall you will find a sequence of letters and numbers that looks something like this: P215/40R15. To determine what rim diameter is required, you need only refer to the last two digits. This number denotes the diameter of the current rim. In the example provided, the rim would need to be 15” in order to fit the tire. This diameter stretches from the lower wheel bead (not including the rim flange/lip) to the upper wheel bead (not including the rim flange/lip). This is where the inner edges of the tire sit on the rim. In order for the rim to be compatible, it must be the exact diameter shown on the tire wall.

Example: 7x15
	7 = Inches (“) between the inner and outer bead of the wheel.
	15 = Inches (“) of diameter between the wheel beads where the tire sits. This measurement does not include the rim flange.

Determining the rim width is not quite as simple, as a physical measurement is required. Since the tire is already mounted on your rim, you can use our online Tire Selector to find out what size of rim your vehicle requires. This tool will tell you what your rim size should be. For the example provided, 7x15 would be the rim size. 15” is the rim diameter and 7 denotes the rim width in inches. The width stretches between the inner bead (not including the rim flange/lip) and the outer bead (not including the rim flange/lip). This number is usually measured in half inches, so results could be 6.0”, 6.5” or 7”. In order for your tire to fit and perform correctly, the rim width needs to be accurate within a few half inches. You should consult with an Auto Service technician before varying from the recommended factory rim width.

Offset

The offset of a wheel is the distance from the mounting surface of the wheel to the true centerline of the rim. A zero offset rim places the mounting surface even with the rim's centerline.

A positive offset means the mounting surface of the wheel is positioned in front of
(to the outside of) the true centerline of the rim. This in effect brings the tire in to the
wheel-well more.

Conversely, a negative offset means the mounting surface of the wheel is behind the true centerline of the rim (closer to the brake side). This will cause the tire to stick out away from the vehicle.

Bolt Patterns

Your rims are attached to your car on bolts. When selecting rims, you will need to ensure you choose rims that match the bolt pattern on your car. Rims have a variety of bolt patterns, and some rims can even accommodate 2 different bolt patterns, which allow them to be mounted on a wider range of vehicles.

Most Bolt Patterns are represented in the following manner: 4/100

The "4" indicates the number of holes in the wheel for the bolts to enter and mount the wheel onto the car. The "100" indicates the diameter of the bolt circle measured in millimeters or inches. (The bolt circle is the area that would be created if you ran a circle around the wheel through the centers of each bolt hole.)

Rim Bolt Patterns

When faced with an even number of bolts, such as a 4- or 6-bolt arrangement, determining the diameter of your bolt circle is easy—simply measure from the center of one bolt hole to the center of the bolt hole directly across from it. On a 5-bolt pattern, this measurement becomes a bit trickier to make without special tools.

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Winter Rims

Winter tires can make a big difference in the cold and snow of Canadian winters. Having separate rims for your winter tires will make the seasonal switch quick and easy.

When you install your winter tires on their own set of rims, you only need to have your tires mounted once. Each season, you save the cost of mounting and unmounting tires from your rims, plus you also eliminate the additional tire wear this can cause. If your car is equipped with a tire pressure monitoring system, by eliminating remounting, you can also avoid damage to the system or its components.

Multi-Fit Steel Rims

Many people only consider steel rims when thinking of a separate set of rims for the winter. But you don't need to sacrifice aesthetics or performance for convenience. Most of today's alloy rims are clear coated with a rust-free, resilient finish to withstand harsh weather conditions. Our extensive selection of in-stock and special order wheels ensures you can get the ideal winter rims for your vehicle.

Wheel Installation

Centrebore

This refers to the center hole in the rim that centers the wheel on the hub of the car. Most wheels are mass-produced, and have a large center bore to accommodate several different vehicles. If this is the case, a hub ring is an essential way to be sure you are properly centering your rim on the hub of the vehicle.

Hub rings are hard plastic or metal rings that fit between the rim and the vehicle's hub. Without hub rings, even if you have the correct bolt pattern and offset, and even if the wheel & tire assembly is perfectly balanced, it is possible to get vibrations because the rim may not be precisely centred on the hub.

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Technical

Alloy vs. Steel

The main differences between alloy and steel wheels lie in their durability and strength.

Steel rims are the standard equipment provided on many vehicles, and are seen by many as a practical choice. These are generally painted black, and often covered with hub caps for aesthetics. Steel rims are economical, and you can find a complete selection at Canadian Tire, including OE rims with an original factory fit, and Multi-fit rims, designed and guaranteed to fit multiple vehicles.

Alloy rims are an investment in your vehicle that improves its looks and performance. Alloy's extra strength material provides longevity as well as positively affecting tire wear. Most high-performance wheels are made of an alloy and composed of aluminum and other metallic substances. The result is that alloy rims are 15-20% lighter than steel, and the weight reduction will improve steering response and handling, as well as acceleration and braking.

Canadian tire offers two wide selections of alloy rims:

Alloy In-Line

In our in-line assortment features multi-fit alloy wheel designs in 4 different styles, including clean 5-10 spoke designs.

Alloy Custom

If you are looking for something more unique, Canadian Tire offers an unequaled source of custom alloy rims through our special order program. Choose from over 2,000 part numbers and 150 different styles to create a look that is truly your own.

Wheel Construction

Your rims may have been constructed in a variety of ways. Most alloy wheels are made in one-, two- or three-piece construction types.

One-piece rims are cast or forged in a mould as a single piece.
Two-piece wheels are constructed from two separate pieces (centre and barrel) that are usually welded or bolted together.
Three-piece wheels are made of three separate pieces: a center, an inside rim, and an outside rim. These pieces are bolted together using high quality fasteners.

The manufacturing method used to create a rim or its parts is integral to the overall quality and performance of a wheel. The most common types of manufacturing techniques employed are:

Low-Pressure Casting is the most common form of rim manufacturing. Liquid metal is poured into a mould and allowed to harden until the finished wheel is cool enough to be removed from its casting.
Counter-Pressure Casting is opposite to low-pressure casting, the liquid metal is not poured, rather it is sucked into the mould using a vacuum. This reduces impurities, making the wheel much stronger than a low-pressure cast rim.
Forging is considered to be the highest quality manufacturing technique, forging compresses a solid piece of aluminum called a "billet" into an aluminum wheel by combining heat with over 13 million pounds of pressure. This process results in a wheel that is both stronger and lighter than standard aluminum rims.
Roll forging is a subset of forging. In this process, a metal blank is run through rollers with impressions sunk in to their surface giving the wheel its final shape. This allows the rim to be produced with less aluminum, reducing weight but maintaining strength.

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Maintenance

Wheel Care

Keeping your rims or wheels clean isn't just about fleeting good looks—it's about protecting your investment. Your brakes transfer heat to your car's wheels. This heat in turn can cause any dirt or brake dust to bake into the protective finish on your wheels. If this happens, there's not a lot you can do besides having your rims refinished or replaced.

Taking good care of your wheels is easy:

Do not use household cleaners or other detergents to clean your wheels. The best wheel cleaning solution is the same mild soap and water solution you would trust on the paint of your car. Clean with a soft, un-abrasive cloth.
Aluminum wheel polish is only suitable for polished wheels. If you use this polish on chrome, painted, or clear-coated wheels, you will only scratch or dull the finish.
Do not use steam cleaners in automatic car washes.
Do not let tire cleaning products get onto your rims.
Clean wheels when they are cool. Heat can affect the soap, causing it to dry on the wheel and become difficult to rinse off.
Clean one wheel at a time. This also prevents the soap from drying onto the wheel.
After your wheels are clean and dry, apply a coat of soft paste-style wax to them. This will create a moisture barrier and help ensure the finish lasts as long as possible.

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