Whether you can safely put bigger tires on stock rims depends on your vehicle.
Generally, speaking there is a maximum size you can upsize to.
And in some cases, the manufacturer’s recommendations will indicate it’s not possible to put bigger tires on stock rims.
Can You Put Bigger Tires on Stock Rims?
You can put larger tires on stock rims, but not by much and you need to be sure you do so carefully. The general margin of safety is up to 20 millimeters larger than the stock rim that was fit on your vehicle according to original specifications.
At the same time, you may need to change your rim size, and this can be a more complicated situation.
That’s why it’s always a good idea to double-check the acceptable ranges with the manufacturer or a local mechanic who has knowledge of these matters.
Read on to learn what you need to know about putting bigger tires on stock rims.
Use Caution: It May Not Be Safe
There’s a good reason why you may not be able to put bigger tires on your vehicle’s stock rims. That’s because you could compromise your car’s safety.
Your speedometer could become inaccurate or stop working altogether.
Bigger tires on stock rims can also impact the stability of your car. Upgrading to bigger tires is mostly popular with truck and SUV owners.
Yet, you don’t want a truck or SUV that can easily topple over or swerve into the lane (and car) beside you.
Another important thing that you’ll impact is your car’s fuel efficiency.
You may no longer get the same miles per gallon when you’re driving on the highway or in stop-and-go traffic.
Plus, you could void your warranty if you go outside of the manufacturer’s recommendations.
Obviously, if you’re past your warranty coverage, this won’t matter. But if you have any kind of warranty coverage left (this includes tires), you will regret voiding it.
Why Upgrade to Bigger Tires?
Enhanced performance and an exciting new look are the top reasons why people choose to put bigger tires on their vehicles.
If the car allows it, upgrading to bigger tires can turn a truck or SUV into a true off-road vehicle.
Tires with mud or all-season traction can help you drive your car on gravel and muddy roads, mountain roads, and places where unpaved roads are common.
Some owners also like to use trucks and performance SUVs for racing and off-roading in recreational areas.
Do I Need Larger Wheels?
This all depends on the recommended rim range for the size of tires you plan on buying.
Provided the tire size will safely fit and operate on your vehicle, you’ll need to find the recommended rim size.
That could be one specific size or a range, such as 15 inches to 17 inches.
To make sure that you won’t compromise the safety, the new rim and tire size should be no more than three percent of your original tire and rim’s height.
If you go bigger than that, you could sustain damage to your suspension. That’s why some mechanics and dealerships won’t recommend or perform tire and rim upgrades.
Once you change the wheel rim and tire size, you have to reprogram your speedometer to ensure its accuracy. This is another move that could be tricky, especially if you don’t have the equipment or instructions on how to do it.
What Else Could I Damage?
Upping your tire and rim size could also put excessive wear and tear on your car’s brakes, powertrain, wheel well, and vehicle frame.
Basically, anything the tires and rims can come into contact with or rub up against is fair game for damage.
You may come across discussions on forums that say you can put bigger tires on stock rims or upsize both on your vehicle.
Remember that forums sometimes contain unsolicited, unverified, and incorrect advice.
Some of the individuals contributing to forum discussions are not experts or trained. It is always best to consult with a professional or your manufacturer’s documentation.
What Else Does Bigger Tires and Rims Impact?
When you increase your vehicle’s tire size and rims, you increase its height. That means you may not be able to pass certain clearances at drive-thrus, under bridges and overpasses, and in tunnels.
You’ll also impact the range of speed your car can go and the vehicle’s balance.
So, your vehicle may become more unsteady on the road, and you could decrease its maximum speed.
Advantage of Using Bigger Tires
For starters, you get increased clearance. This may not be perceived as a pro by some if you live in an area with low clearances on the road.
But if you like to take your vehicle off-road, a higher clearance is a big plus.
You need more space between the bottom or undercarriage of your car and the ground.
There are a lot of rocks, mud, and dirt that could damage your car if the bottom parts are too close.
When you’re up higher, you can also see more.
You can see more objects at a greater distance, whether you’re driving on a paved road or out in the wilderness somewhere.
Some tire sizes also allow you to scale over larger rocks, which may be something you want. It all depends on the terrain where you live and where you take your vehicle.
Drawbacks of Using Bigger Tires
The disadvantages sometimes outweigh the advantages.
First, it’s risky to put bigger tires on your vehicle. You could be negatively impacting your safety and other drivers.
Second, it is expensive. You might have to upgrade your rims and take the time to figure out which size of rims you’ll need.
It’s more complicated or complex than you might think. Doing it yourself is usually not an option unless you have the right equipment and knowledge.
DIY jobs may also be prohibited where you live. It’s best to check with any local codes and HOA bylaws.
You also have to reprogram your car’s speedometer and tire pressure monitoring system. Often, you’ll need the help of a dealership or mechanic to do this.
The costs keep adding up, don’t they?
In addition, you’re going to spend more at the pump.
You’ll find your fuel economy will probably go down. You’ll be visiting a gas station more times a week and filling up your tank more each time.
What do different tire sizes mean?
Tire sizes are usually written as 315/45R15. The first number represents the tire’s width in millimeters.
The second number is the sidewall’s height, expressed as a percentage of the tire’s width.
The final number listed after the R is the rim’s diameter stated in inches.
How do I find the tire size?
To find the tire size, you can multiply the rim size by 25.4. If you have a rim size of 20, multiplying that by 25.4 gives you a tire size of 508 in millimeters.
What other items do I need to check?
When you increase your car’s tire size and rims, you also have to take load balancing into account.
This means you need to know how much your car weighs and what the load capacity of the tire size is.
Going over this number can put you at greater risk for flat tires.