Do Bigger Tires Use More Gas?

The ratings you see on the windows of new vehicles reflect the expected fuel efficiency of your vehicle. These ratings are based on specific tests done in laboratories to simulate different conditions.

While the ratings are achievable when you drive with fuel economy in mind, it is important to remember that several factors can have a significant effect on your fuel consumption. One factor is the size of your tires.

Do bigger tires use more gas? That’s what we want to find out in today’s post. So, keep on reading to learn more!

Are Bigger Tires Better?

One of the first best mods that you can do to your ride is to throw on a fresh set of new wheels and tires, right? You probably want tires that not only will give your ride a better look but will also be a lot more functional than the fuel-saving factory-installed tires.

But you may be wondering… do bigger tires use more gas?

The most important thing to keep in mind when considering bigger tires is your application or the terrain where you will be driving your vehicle. In most cases, you would typically end up using your ride for daily driving, which means you will be mostly on paved surfaces than offroad. 

When driving offroad, an extra bit of ground clearance and aggressive treads would make the tires more functional.

But you also don’t want to have tires that are too large and impractical for daily driving. A too large of a tire would significantly decrease fuel mileage as there is going to be a lot more rolling resistance. The rolling resistance is caused by a bigger tire being heavier in weight. Not to mention that there is more tire patch contacting the ground, creating more resistance and reducing a tire’s ability to roll along easier.

The higher the rolling resistance the more it takes the engine to turn the tires. If the engine has to work harder, it’s going to have to use more fuel to do so.

Which Tire Category Offers Better Fuel Economy?

If you are using your vehicle mainly on-road and want to maintain decent fuel economy, then look for tires that are in the all-season category. The design and tread compound is going to be maximized for traction as well as fuel economy.

The main priority should be traction as several brands and models specifically list all-season tires as fuel-saving. Although the tires will provide better fuel economy on the road, the downside is that you are sacrificing offroad performance.

If you know you are going to be hitting the trails often, then instead of all-season tires, all-terrain-rated tires would be the next best choice for a good blend of on-road and off-road traction and fuel savings. Although some all-terrain designs appear to be more of hybrid tires than all-terrain.

But this assumption is not always right when you factor in tire size. A bigger and heavier all-season tire rated for fuel-saving is still going to create a need for the engine to work harder than a lighter, smaller offroad tire. Also, keep in mind that running the correct tire pressures will boost fuel economy.

What Other Factors of Bigger Tires Affect Fuel Efficiency?

Apart from rolling resistance, here are a few more factors that will affect mileage:

Hysteresis

Hysteresis is a characteristic of deformation of tire material, that the energy of deformation is greater than the energy of recovery.

The features affecting hysteresis are tire construction and design as well as the type of material and quantity used.

An actual rolling tire has two sections, deformed and undeformed. As the tire rolls on the road, the tread from the undeformed section enters the deformed section (compressed area in contact with the road). This means the tread of your vehicle’s tire undergoes compression and expansion, resulting in rolling resistance.

Increasing a tire’s aspect ratio (bigger tires), including its section height relative to its section width will increase hysteresis. The higher the hysteresis the higher the rolling resistance. This could increase fuel consumption. 

If you’re upgrading your tires, you might want to find out the differences between 33 vs 35 tires. 

Tire Design

The beneficial effect of radial-ply designs in reducing rolling resistance is a good example of the influence of tire construction. When compared to bias-ply tires, the radial tires reduce the deformation of the tread in the contact patch, making radial tires a better choice when selecting bigger tires.

Weight

Bigger tires will not only increase compression and expansion of the tread area but also increase rolling resistance. This will make the engine work harder to move the tires, increasing fuel consumption.

Tire Pressure

Maintaining the correct tire pressure is a must if you want to improve fuel efficiency, yet it is often overlooked by some drivers.

This is so because underinflation increases your tires’rolling resistance and, as a result, lowers your gas mileage. We recommend you buy a tire pressure gauge and use it to check tire pressure. Do proper research for the appropriate inflation levels for the new, bigger tires you are planning to put on your ride.

Torque

The stock tires are made to work in unison with your vehicle’s engine, transmission, and axles. The bigger diameter of a bigger tire will affect the overall performance of your vehicle, including weight, braking, acceleration, as well as fuel economy.

The torque curve of the engine will be affected relative to the weight of the vehicle. An engine with a smaller displacement usually produces less torque, which means it has to hit higher RPMs to generate power when you install bigger tires. This will negatively impact fuel economy.

So, Do Bigger Tires Use More Gas?

All factors considered, bigger tires increase contact patch. This will increase performance, of course. But the tradeoff is a higher rolling resistance that will demand more gas to maintain the desired speed. Bigger tires also increase ground clearance, which is good for offroading but will increase wind resistance on the road, decreasing fuel economy.