Effect of Tire Pressure on Fuel Economy, CO2 Emissions and Tire Warranty Miles

In this informative article, we will talk about the effects of tire pressure on fuel economy, CO2 emissions, and tire warranty miles. Before we dive deep into the topic, have you ever wondered, “why do tires lose pressure in the first place?” Yes, there are temperature changes from driving and weather conditions that would cause the pressure to increase or decrease but even a stationary car can lose pressure. Tires are made up of a porous material, which means they would lose air pressure even when they do not have a leak. A study by Consumer Reports showed that a stationary tire naturally loses 3.5 Psi of air pressure over a period of one year. Combined with real-world conditions, the natural air losses would be much more. It is recommended to check your tire pressure every 30 days to maintain the OEM recommended tire pressure. The Cerebrum mobile application tracks real-time tire pressure and provides notifications when there is a need for pressure adjustment. But why are we so concerned about changes in the tire pressure? That’s what we are going to discuss here. 

Effect of Tire Pressure on CO2 Emissions

Since the majority of vehicles run on gasoline, they emit a large quantity of CO2 into the atmosphere. According to the Environmental Protection Agency (EPA), American cars are driven 12,000 miles a year on average. For every gallon of gasoline consumed, it emits about 20 pounds of CO2. This translates to over five tons of CO2 being released into the atmosphere each year. That's a lot of CO2 from just one vehicle. If a properly inflated tire improves gas mileage by 3.3% then you are also saving gallons of gasoline, which will translate to reduced CO2 emission from your vehicle. A reduction in CO2 emissions contributes towards reduced greenhouse gas emissions. 

Although we are slowly making our way towards using cleaner sources of energy with advancements in technology, it will still take years to reach the stage of zero-emission. Keeping that in mind, it is our responsibility to do our part and emit the least amount of CO2 into the atmosphere. The Cerebrum Intelligent Tire system understands the power of combined efforts and provides a tool (mobile application) for each customer to track these metrics daily. There is a special screen in the Cerebrum mobile application dedicated to tracking the CO2 emission from tires. It is like having automatic research analytics on your phone.

Effect of Tire Pressure on Fuel Economy 

A November 2012 study by National Highway Traffic Safety Administration (NHTSA) revealed that every 1% decrease in tire pressure correlates to a 0.3% reduction in fuel economy. While that might not seem like a lot, it can add up to big bucks when it comes to money spent at the pump. You will be surprised to learn the fact that on average only 17% of vehicles on the road have all four tires properly inflated. On another hand, a properly inflated tire improves gas mileage by around 3.3% per gallon.

Let’s explore these facts further by taking an example of a typical sedan with a recommended tire pressure of 32 PSI and a rated fuel economy of 25 MPG. 

Tires naturally lose 1 - 2 PSI every month. If the driver of this car goes 1 month without checking the tire pressure, the resulting fuel economy on average will drop to 23.1 MPG. 

Similarly, the temperature drop of 50 degrees F from summer to winter, translates to about 5 PSI underinflation. When combine with the extra rolling resistance in winter weather, the fuel economy will reduce to 20.3 MPG. If we consider a gas price at $3.5 per gallon and annual mileage of 13K miles, then from a 5 PSI underinflation the driver is losing $56 in gas, in 6 months. 

Effect of Tire Pressure on Tire Warranty Miles 

Now you might be wondering how tire pressure can impact a tire’s warranty miles? Well, we know that improper tire pressure wears down the tire rubber at a faster rate. The pattern of tread wear depends on whether the tire is underinflated or overinflated. When the tire is underinflated, the weight of the vehicle is put on the shoulders of the tire. Driving for too long with underinflated tires results in excessive tire shoulder wear. Similarly, the overinflated tire bulges the center tread and puts all weight of the vehicle at the center area. This, as a result, causes the center area to wear out faster. 

Every tire has a tire mileage warranty defined by the tire manufacturers. That means you will get the optimum performance from the tire throughout the defined tire mileage before it reaches the final 2/32nd of the tread. Such warranty is only valid when the tire is worn evenly. Improper wear of tires from underinflation and overinflation results in losing these valuable miles and also your possibility of getting a refund from the manufacturer in the event of a premature failure. 

For more insight, let's take a vehicle that is driven on an average of 13K miles per year and has a 50K warranty miles on the tires by the manufacturer. An underinflation of about 3 PSI in a tire for a year's time will translate to 155 warranty miles loss for each tire. Combined with road conditions and driving style, this number will translate to way more. 

Cerebrum mobile application tracks your tire's current pressure, along with other metrics, and provides you with a simple ‘Cost of Inefficiency’ screen (This includes the cost of excessive gasoline usage and cost of tire mileage loss) and ‘Warranty miles loss’ screen. Such metrics teach the user to maintain the health of their tires and get the most out of their bucks.