Car wheel parts: Basic parts of a car wheel

Every automobile, from a Ferrari to a Ford Pinto, depends on the wheel, the most basic of machines. The wheel might be the greatest invention that man has ever invented; there is no avoiding it right next to the fire (no pun intended). Cars and trucks would only be pricey yard ornaments without wheels and tires.

Wheels and tires serve the same purpose on every type of vehicle. The only distinctions are in terms of construction, size, and style. The fundamental components of a car wheel and tire are described below to broaden your understanding of cars, trucks, and how they operate. Knowing more about your car will help you take better care of it and keep it operating for a long time.

Car wheel parts Basic parts of a car wheel

Well, in this article, I’ll be discussing the various parts of a car wheel.

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What is a car wheel?

The earliest round building components that move an automobile are known as wheels. They are positioned vertically beneath the truck, which permits movement while simultaneously supporting big loads and the vehicle.

The function of a car wheel

Every kind of vehicle, from little vehicles to big trucks, relies on its wheel as its basic operating mechanism. Cars have been altered in recent years to have a variety of bodies, designs, and sizes. Some auto parts are now outdated, expired, or have been replaced with newer models.

A simple circular component designed to rotate on the axle bearing is what the wheel is. Wheels and axles work together to make it simple to move heavy things, which reduces the amount of movement or transit required to sustain loads or operate machinery.

The car is moved from one location to another by these wheels, which provide rotating motion. Cars and trucks would only be pricey yard ornaments without wheels and tires.

There are numerous parts to a wheel, each of which has a specific function, but not every driver is familiar with all of them. We’ll look at the fundamental components of a car wheel and tire below to offer you a quick understanding of these elements.

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Parts of a car wheel

The hub, spokes, and rim make up the wheel. the region where the lateral surface of the rotor, the lug bolts, and the axle seat all come into touch. The following are the various parts of a car wheel:

  • Wheel bearing
  • Wheel rims
  • Tire
  • Wheel hub
  • Wheel fasteners
  • Barrel
  • Bolt circle
  • Outer lip
  • Flanges
  • Centre bore
  • Valve system
  • Spoke
  • Center cap
  • Beads
  • Lug hole


Wheel bearing

Antifriction bearings, which produce a low-friction connection between the revolving wheels and the stationary vehicle, are a common type of wheel bearing. The inner race, rolling element, and outer race are the three fundamental components of this type of bearing.

Wheel bearings are primarily used so that the wheels may rotate smoothly and with the least amount of resistance. To help reduce friction while the wheels spin, car wheels feature hubs in the center, where the wheel bearings fit snugly within the hub and travel on a metal axle shaft.

When selecting a wheel bearing, care must be taken to take into account the kind of load, the maximum bearing speed, and the location of the bearing on the vehicle.

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Wheel rims

Typically, confusion develops between the rim and the wheel. Sometimes the wheel is referred to as a rim and vice versa. Let’s make a distinction between the two: the rim is only a portion of the wheel, but the wheel is composed of the tire and other parts, in addition to the rim.

The tire is secured in place by the skeleton’s outside edge, which is known as the rim. Its cylindrical shape enables the annular housing to be secured to the wheel and sealed. To seal the air inside tubeless tires, the tire and rim must be properly assembled. Between the rim and the tire on older models of cars were tubes.

To endure the weight and force of the car, the rims are made of sturdy metal, such as steel. The size of the car tire is determined by the rim’s width and diameter. Custom rims are available as aftermarket car parts. These custom rims cost extra and can be colored and decorated whatever you choose.

The barrel of the rim provides a platform for mounting the tire. The type of wheel mounted is determined by the center of fall, which is the inside diameter of the cylinder. The drop center for front-mounted wheels is close to the front of the wheel. Rear-mounted wheels, on the other hand, have fall centers close to the back of the wheel.

The barrel edges are formed into flanges to prevent tires from slipping when driving. They have flat pieces within called beads. The tire’s edge rests on this surface created by these flat areas.

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Everyone is aware that tires are designed to transmit traction, torque, and braking forces to the road surface as well as carry the weight of the vehicle and maintain the direction of travel. To carry out these tasks, tires are filled with compressed air and built of flexible rubber.

They are regarded as a component of the suspension system. In essence, tires are covers that keep wheel rims from rubbing or making contact with the ground. The threads that directly touch the ground and degrade with time are the fundamental components of a tire.

Typical threads feature patterns, which are grooves and notches. This design is intended to maximize tire-ground contact friction and steer water and other debris away from the wheel.

Read more: Understanding tube and tubeless tires

Wheel hub

The hub, which is the most important component, is where the wheel is attached. It has a hole in the middle that is used to mount the wheel to the axle. When the driver presses the brake pedal, the brake discs rest against the wheel hub to ensure that the vehicle brakes.

The center hole is covered by a detachable center cap on the outside of the wheel. Typically, a wheel disc that is either removable from or permanently attached to the rim serves as the link between the hub and the rim. Spokes are used on some automotive wheels to join the rim and hub. The structural integrity of the wheel is also provided by the spokes. Modern wheels typically have styled spokes for aesthetic appeal.

Make sure the central hole on an aftermarket car wheel is the same size as the OEM or OE wheel before you buy it. It will cost more to use wheels with a larger central bore since hub-centered rings are required to close the gap. The center disk is situated just outside the center cap on spoked vehicle wheels. The wheel offset is determined by the depth of this disc about the centerline.

On the middle disc, lug holes are commonly drilled to produce bolt circles. The holes are known as “lugs” where the wheel nuts are fastened. The bolt circle diameter is the size of the bolt circles made by the lug holes (BCD). The bolt pattern is determined by this dimension and the number of holes.

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Wheel fasteners

The method by which the rim is fastened to the hub or axle flange is a critical aspect of the design of the wheel and tire. On every kind of vehicle, the wheel studs are employed as wheel fasteners in the hub or axle flange. These are probably pressed into a hub or flange for a tighter union and are threaded bolts or studs.

To prevent the stud from fully piercing the hole in the hub or flange, the head of the stud is typically wider than the hole. The center of the hub or flange is elevated slightly and placed in the center of the rim to properly center the wheel.


The barrel refers to the area of the car wheel that lies between the outboard face and the inboard rim edge. The barrel’s function is to provide a surface on which the tire can be mounted. The drop center, which influences the type of mount wheel, is the barrel’s inner diameter.

The drop center is close to the front of the wheel in front-wheel drive cars. On the other hand, a vehicle with rear-wheel drive has drop centers close to the back of the wheel. Flanges formed by the barrel’s sidewalls prevent the tires from slipping as the car is in motion.

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Bolt circle

The bolt pattern of a wheel is often known as the bolt circle or pitch circle diameter. This is the space that the lug bolt generated. The bolt circle is calculated by multiplying the number of lugs by the diameter of the fictitious circle the lugs’ centers form.

For instance, a 54′′ bolt pattern would have 5 lug bolt holes and a 4-inch BCD. Cross-fitting wheels made for multiple automobile manufacturers is challenging since bolt circles typically vary between the wheel and car manufacturers.

Outer lip

The most repairable section is the outer lip, which is the portion that will most likely collapse when a wheel strikes a pothole. Up until the tip touches the face of the wheel, the lip technically can be deeper or larger. A deeper outer lip is more vulnerable to damage from impacts since the spokes cannot support it as well. The distance from the wheel face to the edge of the outer lip, which is on the outside, is specified.

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A wheel flange often acts as a connection to connect the wheels of the vehicle to the axle. These are mechanically locked to the spindle’s end or the drive axle. Additionally, they are on the sides of the wheel to stop the tire from unduly slipping.

Car wheels have traditionally been mounted using wheel flanges and lug nuts. The tire will remain attached to the wheel even in adverse weather or on uneven surfaces thanks to the flanges that are found on both ends of the wheel.

Centre bore

The wheel is correctly centered on a vehicle by the machined aperture in the center of the wheel. A wheel must be hub-centric to lessen the likelihood of vibration. The functional space that extends above the axle and bears the weight of the car is often contained in this void.

The replacement wheels cannot be installed if the hub collar’s diameter is greater than the central bore. The wheel can be fitted similarly if the center bore is greater than the hub’s diameter, but an unintended diameter difference would be challenging.

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Valve system

Car tires’ valve systems allow for inflation and deflation. The tire pressure monitoring system is built into the valve mechanism on car wheels, allowing the driver to always be aware of the tire pressure level. The valve’s purpose is to keep air or nitrogen inside and keep it from escaping. As a result, it is crucial for maintaining tire pressure and safe driving.

Wheels often have two valve stems for a pair of purposes. The first involves using a valve stem to pump air in, and the second involves refilling nitrogen air. Simply put, one valve stem is used to cleanse ordinary air, and the other stem is utilized to pump nitrogen.


The spokes are crucial in securing the plate in the wheel’s center to the rim of the wheel. The lugs and bolt holes used to attach the wheel to the car are kept here. Additionally, the spokes protect the outer edge and shelter it from slight blows. There are countless variations of these spokes. The traditional type has five spokes, however, some also have elaborate decorations or only have three. The material and design have an impact on the stability and strength of spokes.

Center cap

The rims and tires of the car are shielded from dirt and sunlight by high-quality car wheel center caps. These automobile wheel covers are an excellent purchase, especially for drivers who leave their cars parked in public areas.

The spoke-filled middle of the wheel is where the center cap is located. The center cap on some models can be taken off. But the majority of rims don’t have detachable center caps. While a wheel can be used without a center cap and still operate properly, the center cap gives the wheel a more finished and uniform appearance.


Tire beads provide the primary function of securely fastening the tire to the outside of the wheel. To do this, the wires’ pressure is used to force the rubber firmly into the wheel’s frame. The wheel that will transport energy also includes beads.

If the beads are broken, the energy may transfer improperly and shake the whole car, especially when it is moving quickly. Because they provide an airtight seal against the wheel and enable a more effective transfer of forces while the automobile is moving, beads are crucial.

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Lug hole

On the center disc, the lug hole is typically machined to resemble a bolt circle. It is through these holes that the lug nut is fastened. The voids that the center cap typically covers are known as lug holes. The bolt circle diameter is the size of the circle made by the lug holes.

The threaded wheel stud on the vehicle’s axle is connected to the wheel hub by the lug nut, which secures the wheel in place and centers it correctly. It is a kind of nut fastener with a conical (tapered) end or a round end.

Watch the video below to understand the various parts of a car wheel:

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How to read tire sizes

When looking for new tires, you may see size designations like 235/75R15 or P215/65R15. If you don’t know how to interpret these labels, they can be complicated, but once you do, they become easier to understand. There are three digits and occasionally letters to the left of the slash symbol. The numbers indicate the tires’ width from sidewall to sidewall in millimeters. The more road the tire contacts, the higher this figure will be. The tire type is indicated by a letter on the left side. You may see the following letters:

“P,” or a tire for a passenger car. Additionally, this document informs you that the tire was manufactured by American standards. If there is no letter, it was made by European standards. The load capabilities of the two types vary.

LT stands for a light truck. Light vehicles are supposed to utilize tire sizes that begin with these letters. To handle trailers and big loads better, they will have greater psi recommendations.

For a specific trailer, use “ST.” Only trailer wheels can use tire sizes denoted by these letters.

We can determine that a tire is for a passenger vehicle and has a 215-millimeter width by looking at one with the size P215/65R15.

There are two numbers, a letter, and two additional numbers to the right of the slash symbol. The aspect ratio, or the ratio of the tire’s height to its width, is shown in the first set of numbers. These figures are 65 in our P215/65R15 example, indicating that the sidewall height of the tire is 65 percent larger than the tire’s width.

The middle letter to the right of the slash, which indicates the tire’s manufacturing process, is typical “R,” or radial. This indicates that the tire’s layers are radially oriented across it. The last digit is significant since it indicates the size of the wheel that the tire fits. This number is 15 in our case, indicating that the tire will fit a 15-inch diameter wheel.

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What Parts Are in A Car Wheel?

Parts of a Wheel

  • The hub, rim, and tire together make up the wheel.
  • The area of the wheel that the tire wraps around is called the rim.
  • The tire and the mounting structures take on their shape thanks to the barrel.
  • The wheel’s outside edge is known as the outer lip.

What Is the Part of The Car Over the Wheel Called?

Only the panels covering the front wheels are typically referred to as fenders in the current US car industry nomenclature. The fender forms the wheel well surrounding the tire on broad-body automobiles that conceal the tire and is not readily visible from above the car body.

What Holds a Wheel on A Car?

The threaded fasteners that hold on the wheels of various cars are known as wheel studs. They are frequently installed through the brake drum or brake disk directly to the vehicle hub on a semi-permanent basis. To hold the wheel in place, lug nuts are screwed onto the wheel stud.


What Are the Parts of a Tire?

Tires are made up of many different parts, and it’s important to understand how they work.

  • Inner Liner.


What Are the Parts of a Wheel and Axle?

One of the six different types of simple machines is a wheel and axle, which consists of an inner and an outer ring or cylinder called the axle and the wheel, respectively. When a force is given to either the wheel or the axle, these two components, which are rigidly coupled, move in the same direction.

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How Do You Replace a Wheel Stud?

Watch the video below to learn how to replace a wheel stud:


What Are Wheel Fasteners?

The most crucial hardware component on any car is its wheel fasteners, yet they are frequently the least understood and valued. They can consist of hub-mounted studs and detachable nuts or wheel bolts that thread into the hub.

How Much Does a Wheel Stud Replacement Cost?

Replacement wheel lug studs typically cost between $73 and $89. The cost of labor is expected to be between $61 and $77, while the cost of the parts is $12. Taxes and other costs are not included in this range, nor are your particular vehicle or geographic area taken into account.

How Much Is a Wheel Hub?

These days, a complete-unit hub bearing is used in the vast majority of cars. Since hub bearings typically cost between $80.00 and $300.00, the cost of the bearing represents the majority of the overall cost in this case.

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What is the hub of a wheel?

The middle of the car’s wheels is where the wheel hubs are positioned. They are specifically located between the driving axle and the braking drums. In essence, wheel hub assemblies serve to join the wheel to the car’s frame. The system includes bearings that enable the wheels to move smoothly and softly.

What Are 5 Examples of A Wheel and Axle?

A doorknob, a screwdriver, an egg beater, a water wheel, an automobile’s steering wheel, and a crank used to raise a bucket of water from a well are some examples of the wheel and axle.

What Do a Wheel and Axle Look Like?

The wheel and axle are made up of a wheel, which is a round disk with a rod running through the middle of it, and an axle. This mechanism typically works against gravity to move things by using torque and rotational momentum. Gears and the wheel and axle basic machine go hand in hand.

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Can You Replace a Wheel Stud Yourself?

If you’re like everyone else, you haven’t used a torque wrench to tighten the lug nuts on your automobile. You’re the type of man who will “throw all the muscle you can into it,” and right now you’re looking at a busted wheel stud. Tire bolts are a simple, inexpensive DIY project that takes approximately an hour to complete.

Can you drive a car with broken wheel studs?

It is unsafe to drive with a damaged wheel stud because, once one breaks, it increases pressure on the other studs, eventually leading to their failure. Since the wheel will start to wobble and may fall off, driving with a broken wheel stud is risky and may result in an accident.

What Causes Broken Wheel Studs?

Low torque is the most frequent cause of stud breaks on stud-piloted wheel systems. The wheels ride on the studs and shatter them when the wheel system is loose. Wheels will become loose and shatter studs for the same reason if the studs are over-torqued and then yielded.

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How Do You Fix a Broken Wheel Stud?

Watch the video below to learn how to fix a car with a broken wheel stud:

Do Wheel Lug Nuts Wear Out?

The purpose of wheel studs is to keep your tires and wheels securely fastened to your vehicle. These durable steel parts typically don’t deteriorate or wear out. However, other problems might cause these parts to wear out or fail because the wheel stud is exposed to the environment and undergoes considerable everyday stress.

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How Much Does It Cost to Get a New Wheel?

Replacement wheels typically cost between $708 and $719. While parts are priced at $664, labor expenses are predicted to range between $44 and $56. Taxes and other costs are not included in this range, nor are your particular vehicle or geographic area taken into account. There might be more repairs required.

How Long Does a Wheel Hub Assembly Last?

Wheel bearings typically need to be replaced after 85,000 to 100,000 kilometers. Wheel bearings can last a long time in some cars, but they can also wear out very fast in other cars.

Can I Replace a Wheel Bearing Myself?

By changing your wheel bearings rather than having a mechanic do it for you, you can save money. However, you should exercise caution since, despite their diminutive size, bearings are crucial.

In conclusion

As we previously stated, wheels are a component of cars that have always been used. These rotating motion-generating circular devices are mostly in charge of transferring the car from one location to another. Therefore, wheels are a critical part of any car.

That is all for this article, where the parts of a car wheel are being discussed. I hope you learn a lot from the reading, if so, kindly share with others. Thanks for reading, see you around!