Can a different tire size be put on the same rim?

The answer to this question is yes. Even though all cars come with a predetermined size of rims, the tire itself is a separate component of the vehicle’s wheel set-up.

This means you can place a different tire size on the same rim. However, before you begin replacing your tires with different sizes, it is important that you understand every aspect of making tire size changes.

To start, here are some essential things that you need to know about changing the tire sizes on your rims.

What wheel properties count when you want to change the tire size?

When you want to make a change in the size of your tires, you need to know what properties to look for. In fact, you need to know how to read the tire size properly in order to understand the basics.

For instance, every tire has a serial number that is designated for that particular tire. Here is what this number looks like and a brief corresponding description of what it means.


  • 185 – Width of the tire in Millimeters.
  • 65- Percentage of tire width (Sidewall height)
  • 15- Diameter of the Rim

As you can see, all characters in this series of numbers have a specific meaning. These numbers are used to determine if the size of a specific tire size will fit safely on the rim.

What are the advantages of changing the tire size?

Changing the tire size on your rim can make a huge difference. Based on the size that you select, here are 3 advantages.

1. Improved Performance

When you decide to choose a bigger tire, you can take advantage of improvements in performance. This is normally achieved by improving the tire’s aspect ratio.

For instance, if you increase the dimensions of your tires, you are also extending the contact patches. Simply put, whenever your contact patches spread over a larger portion of the pavement, your tires will grip the ground better.

Here are some of the improvements in performance that drivers tend to experience right away.

  • Grips road better when brakes are applied
  • The driver has better control when accelerating
  • Making sharp turns is easier

The size of your tires can also determine if your vehicle is ready for the road during heavy snowfalls. In these situations, however, you want may want to buy smaller tires.

This is because smaller tires are less susceptible to issues like hydroplaning when the roads are wet. The smaller tires make it a lot easier to slice through slush and snow on the road.

2. Looks Aesthetically Pleasing and More Expensive

The tire size change is not only about safety for some drivers. In fact, if you want to make sure the tires look better on virtually any car, you should replace narrow tires with larger ones. The larger tires usually look a lot more sleek and elegant.

What are the disadvantages of changing the tire size?

As you can see, there are advantages to using larger tires on your vehicle. However, you should never go overboard. For instance, if your tires are too big, the risks of sustaining damages are higher. Here are some of the disadvantages of changing the tire size.

  • Cuts on tires caused by rubbing against the metals on the vehicle
  • Wider tires subject to more friction
  • Adversely impacts on transmission
  • Odometer or Speedometer misplaced
  • Decrease in toque
  • The ride is not as smooth

Does tire size really affect car performance?

Yes, the changes in tire size can make a difference in a number of different ways. For example, if you increase the size of the tires on your vehicle, you may begin to experience problems with your transmission.

For instance, if the tire size is larger, it can affect the gear’s ratio. Based on the significance of these changes, it may even result in the tires turning more slowly than before.

The transmission may also require more power to accelerate since it may require more energy to function properly. This is also why it causes pressure on the gear’s ratio.

It is also important to note that there are other performance issues that can be caused by different sizing, including problems with the speedometer, anti-lock braking system, and the stability of the system’s calibration.

Is it legal to have different tire sizes than the ones specified by the manufacturer?

If we take the law in the U.S. This law applies in most states and has restrictions on the tire’s width. For instance, the width of the tire cannot stick out further than the car’s fender.

One of the best places to find additional information about these laws is on each state’s site.

Can you pass MOT with a bigger tire size?

Yes, you can pass MOT with bigger tire sizes. In fact, it is not illegal to put tires from different manufacturers on the vehicle. However, your car will fail the inspection if you place 2 different size tires on the same axle. (across the same axle).

When this is the case, it affects the stability and the handling of the vehicle. In essence, it is just like driving with a bald tire and a new tire.

What fines are there for driving with bigger tire sizes?

The fine for a driver with bigger usually varies from state to state. Based on information posted on, the fine in the state of California is approximately $90. Or, in the state of Virginia, the fines for improper or adequate tires can range from $30 to $81.


Before you change the tire sizes on your rims, you need to do your research first. The tire sizes that you choose can make a huge difference in safety, your vehicle’s performance, and its overall looks. Therefore, you need to understand every aspect of which size is best for your rims.


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