Rims vs. wheels: How to tell the difference

“Hey, check out my new rims!” quips your car enthusiast friend. But what part of the vehicle are they referring to? If your mind jumps to car wheels, you’re not alone. When it comes to the question of rims vs. wheels, the terms are often used interchangeably. However, the rim is just one part of the wheel — and an important one at that.

What are wheels?

To understand the difference between wheels and rims, it helps to know how automobile wheels work. Let’s start with the basics. While sometimes people think of tires when they talk about wheels, technically your wheels and tires are separate entities that ultimately combine to form the tire-wheel assembly.

Rims play an important role in this setup. As the outer edges of the wheel, your rims secure the tire on to the wheel by forming an airtight seal. But rims are only one part of the wheel equation. In addition to rims, wheels are comprised of other important features:

• Wheel bearing: This is the part of the wheel assembly that connects the wheel to the axle.
• Lug nuts: Located around a wheel’s center, these nuts secure the wheel to the vehicle. 
• Center cap: These caps help keep dirt and grime away from the wheel bearings and lug nuts. They often sport a manufacturer’s logo.
• Hubcap: Larger than center caps, these disks are hammered or clipped on the hub of the wheel, covering the lug nuts. Hubcaps used to be more common, helping protect steel wheels from the corrosive effects of winter weather, road salt and other harsh chemicals. Nowadays, wheels are increasingly made of aluminum or metal alloys, which tend to better protect against corrosion, making hubcaps less of a fixture.
• Spokes: These are the metal arms that connect a wheel’s center to its outer reaches, such as the rim and the barrel.
• Barrel: While your rims are the outward-facing edge, the curved portion of the wheel outside of the spokes is known as the barrel.
• Wheel cover: A wheel cover helps protect the entire surface of the wheel. Wheel covers are often designed to make the wheel look more appealing and may also be used as a cosmetic fix for minor scratches.

What are rims?

As we mentioned, the main difference between wheels and rims is not technically a difference at all: rims are simply one important part of the wheel. Of course, in popular culture the phrase “Nice rims!” has long been used as shorthand for complimenting someone’s wheels, particularly in reference to a sharply designed or intricate wheel cover. But what we’re talking about here is what rims actually are: the two outer edges of each side of your wheel.

What do rims do?

As the edge points of contact between the tire and the wheel, rims help hold tires properly in place. As stated, they also help maintain an airtight seal between the tire and the wheel.

For these reasons, your rims play a crucial role in supporting the entire wheel assembly and its place in your car’s suspension system. If you drive over a bump or pothole, the rim is the part of the wheel that receives the initial impact after it passes through the tire.

You may think of your tires and rims as the front line of defense against the rigors of the road. If your rims get banged or dented, it may affect the performance of your vehicle, from flat tires and reduced handling to distracting vibrations inside the cabin.

What do rims look like?

If you look at a wheel from the top without a tire on it, you’ll see that it dips down in a “U” shape, which continues along its circumference. The rims are the upturned stems of this U-shaped design. The outermost edges of the tire, known as “tire beads,” press against the rim when inflated to form the tight seal.

What are rims made of?

Your rims are made from the same alloy or metal as the rest of your wheel. They’re also often specially treated with a protective coating during the manufacturing process to help extend their longevity.

How to know what size rims you have?

Knowing how to determine rim size can be helpful, because wheel size and tire size depend in part on the diameter of the rim.

Your rim size can be found in several places. Firstly, you can check the sidewall of the tires that came with the wheel. If you no longer have those tires, the information may also be found in various places such as the inside frame of the driver’s door, on the gas tank hatch, on the glove box door or stamped on the back of the wheel itself. When in doubt, checking your owner's manual is always a good idea.

If you spot a numeric sequence like “16x6 5-110,” the initial two dimensions give you the diameter of the rims and the width between them (16 inches and six inches in this case). The other two dimensions refer to the number of bolt holes and their diameter (five lug nuts in a circular formation measuring 110 millimeters at its widest point in this case).

Do rims come with new tires?

Generally, when you replace your tires you don’t also need to buy new rims, unless you’re investing in a wheel-tire combo, possibly due to damage to your rims.

How do rims become damaged?

Rims can become dented by curbs or potholes and corroded by road salt. Similar to tires, they also tend to wear with age. Signs of a damaged rim may include sudden changes to handling, vibration when steering, problems with your wheel alignment and tires that repeatedly deflate. It’s generally best not to leave any concerns with your car’s suspension to chance. Consider asking a trusted mechanic for advice.

The difference between wheels and rims

Let’s return to where we started: the difference between wheels and rims. As explained above, it comes down to a matter of detail. The wheel is the metal unit that attaches the wheel hub to an automobile via an axle, while rims are the outermost part of the wheel assembly. Perhaps think of it this way: “rim” means “edge,” and rims are located on the edges of your wheels.

In the more colloquial sense, “rims” may refer to the wheel covers you might sometimes see on a car, typically added for aesthetic reasons. Though somewhat of a misnomer, this correlation might possibly have come about because the rim size does dictate the size of wheel cover required.

In summary

The difference between wheels and rims is more than simply semantic. If it weren’t for your rims, your tires wouldn’t be properly secured to your wheels, leading to a ride that is shaky and potentially dangerous. Understanding rims vs. wheels may also make it easier to explain any issues with your wheel assembly to your mechanic. Although actual rims may not have the decorative flair of modern-day wheel covers, this crucial wheel component still deserves its chance to shine.

Steve goes to a car lot in Hamilton to browse and find himself a new car. He walks among all the vehicles on display, considering their horsepower, fuel economy, size and whatnot. But one car catches his attention not because it ticks all the boxes on his list of what he is looking for in a car but because it has the most beautiful wheel rims he has ever seen. Long, clean lines, sturdy constitution, black coat of paint… And it complements the car’s overall appearance – he is simply smitten! But what is the deal with wheel rims? What are rims, and why are they so important in a car? Stick with us to find out!

You may not think automobile wheel rims are that important for driving a car in Hamilton – some people tend to focus on them because of their aesthetic appeal – but they certainly play a vital role in the whole driving experience. Why? They allow your car to roll so you wouldn’t get too far without them. Without undamaged and quality wheel rims on a carmounted, your car can only be stationary – which is questionable – and you certainly haven’t bought a car to just sit in your garage or driveway in Hamilton. So, let’s examine wheel rims, their varieties and why they matter.

Note: If you need consultation regarding buying new car rims in Hamilton, visit our auto service shop. Our licensed and experienced mechanics can help.

Rims and more: the anatomy of a wheel

The rim is an essential component of a wheel (although most people consider them one and the same thing):
1) Outboard face/the “spider” – the face of the wheel which makes the design visible when looking at the vehicle and provides structure for the wheel
2) Center bore – an empty hole in the center of the wheel which is often covered by a center cap with the manufacturer’s logo so it isn’t visible when the wheel is on the car
3) Center disc/plate – the central section around the center bore that contains the lug holes; it bolts to the wheel hub, while the spokes connect the rim to the plate
4) Spokes – the structures that connect from the plate to the edge of the rim; they play a large part in determining the weight and strength of a wheel as are a huge variety of spoke patterns, with different spoke counts, diameters, lengths, and shapes available
5) Rim – outer diameter of the wheel usually measured when discussing the size of a wheel
6) Bolt circle – the circle that is created by the centers of the lug holes, where the lugs affix the wheel to the hub
7) Valve stem bore – the hole that allows air to be added to the tire; the valve stem itself be made of rubber or metal.

Wheel rims are made from a few different materials, which does not only affect the look of the wheels but, more importantly, their strength, weight and durability. Here are the most common types:
1) Steel – simple and cheap, usually essential in the design and fitted to low-cost cars; a hubcap often covers them to add some style and are often heavier than more costly equivalents
2) Aluminum alloy – strike a solid balance between strength, weight, durability and cost, so all types of cars from every automaker are fitted with aluminum wheels, from sedans to trucks, to luxury cars
3) Carbon fibre – extremely light and strong, but brittle (a single impact with a curb or piece of road debris can render them useless); still scarce, but more and more vehicles are available with carbon fibre wheels.

(Look at our infographic to get a clearer picture of the differences between steel and alloy wheels.)
Strictly technically speaking, wheels provide a means of mounting and affixing the tires to the vehicle through which the engine’s power is transferred to the ground. As the engine generates power, it moves through the drivetrain to the wheels, which bolt to the wheel hub and rotate around the axles. For the wheels to turn and propel the car forward, you need to have friction provided by the tires in direct and constant contact with the ground under the car. The car gets the leverage it needs to move by the wheel, transferring power from the axle and the hub to the tires. The larger the wheel is compared to the engine’s power, the bigger the leverage and the faster the car moves.

What to consider before installing new wheels

Moreover, looks aside, the car’s wheels significantly impact its alignment, handling, braking, ride quality, and acceleration, as well as the calibration of the speedometer. Therefore, before installing new wheels on your car, consider these things:
1) Make sure it fits in the wheel well
2) Consider the correct backspacing (the width of the wheel and the location of the mounting plate)
3) Ensure it matches your vehicle’s wheel bolt pattern
4) Determine if there is an adequate selection of tires that fit the new wheels
5) Make sure the wheels aren’t rubbing anything on the vehicle, especially while turning or under suspension compression.
Another major thing to consider when buying car wheels is their size. If you want to replace wheels on your car, you have to make sure that your new wheel and tire are as close in diameter as your old wheel and tire.
Following this particular rule will benefit you in a few ways. For example,
1) You won’t have to spend more money to make additional modifications to your car and/or wheels to make them fit
2) You won’t risk your safety since you will have control over your vehicle on the road
3) Your acceleration times and fuel consumption won’t suffer (or might get marginally better).
Finally, despite being solid pieces of metal that can support hundreds of kilos of weight, there is a number of things to consider when it comes to wheel rims and wheels as a whole. Aside from size considerations, durability and strength are crucial to staying safe behind the wheel. Lightweight wheels may spin up faster and turn more readily but are more susceptible to denting, cracking, and other damage. Heavy wheels might be stronger and more durable but can reduce fuel economy. Every vehicle type has different needs, so you need to find the wheels that will suit them best.

Essential facts about wheel rims

Knowing how wheel technology has changed over time helps us to understand why wheels are designed the way they are and how to choose and maintain the best rims for a particular vehicles. Here are some interesting facts about the history and design of rims:

1. Andre Michelin invented modern rims.

The basic design of modern car wheels relates to the invention of removable pneumatic tires in 1891. Andre Michelin, one of the co-founders of the famous tire brand, was working in his rubber factory one day when a cyclist came in and asked if he could help repair a damaged tire on his bike. Andre and his brother Edouard struggled to remove the tire because it was glued to the wheel. The two of them decided to build something that would be easier to maintain, so the removable tire concept was born.

2. Aftermarket wheels are a relatively recent invention

Until the 1950s, every brand and type of vehicle had its own specific and proprietary wheels. In the 1950s, American Racing Equipment began to design and manufacture a series of aftermarket rims, i.e. rims that could be fitted on multiple car types and were not affiliated with any specific automobile brand. We now take aftermarket wheels for granted, but they were a bold new concept when American Racing Equipment first introduced them.

3. Steel and alloy rims each have pros and cons

Rims are generally made of either steel or alloys of aluminium or magnesium. Alloy wheels are rising in popularity and many car enthusiasts are outspoken about their superiority over steel. However, both materials have their benefits. Steel is cheaper and extremely sturdy, making them an excellent choice for monetary savings and durability. On the other hand, alloy wheels are lighter, allow easier handling and mileage, and make for a much smoother ride.

4. It is essential to clean rims

Rims are susceptible to corrosion over time – regardless of whether they are made of steel or alloy. Proper care and maintenance of rims, including thorough, regular cleaning, are essential. Two main agents of rim corrosion are brake dust and the metal shavings shed from the brake discs every time you slow down or stop your car. Luckily, cleaning rims requires no effort or special detergents or equipment. Sponging them down with a good car shampoo or clay-based cleaner will do the trick.

When thinking about changing your wheel rims, it’s wise to consult an experienced professional to ensure you select a design compatible with your vehicle. And we are just the right kind of mechanic for that. Come to our repair shop in Hamilton today, and let’s upgrade your automotive pet together!

We are located only 5 min driving North of St. Peter’s Hospital – Hamilton Health Sciences and 6 min driving North of Gage Park.

Since 2005, we have built a reputation for delivering exceptional automotive repair services and outstanding customer care.
Our commitment to excellence and dedication to our clients have made us a trusted name in automotive care.
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Our comprehensive range of services ensures that your vehicle remains in top condition, covering all aspects of automotive repair and maintenance.
When you choose CRS Automotive, you’re choosing a team that genuinely cares about you and your vehicle.