Eco-Tip Challenge: Optimize your gas mileage by checking your tire pressure monthly
July 19, 2011 | by: Charlene Harper, PE, LEED AP
Having too little air in your tires can significantly decrease your gas mileage and will also cause your tires to wear out quicker! Low air pressure increases the area of the tire which comes into contact with the ground and results in more drag, decreased gas mileage, and faster tread wear and tear.
Let’s assume we are talking about a typical tire pressure recommended range of 24 – 32 psi. Filling your tires to the higher limit of the safe range (i.e. keeping them at 32 psi) can increase your gas mileage by 3 – 4% compared to keeping them at the lower limit. And on average, gas mileage decreases 5% for every 2 psi pressure drop compared to the lower pressure limit for your tires. So, what will that feel like as you drive? The lower limit of 24 psi will give you a softer ride than the upper limit of 32 psi—but though the ride may be slightly rougher, think of all the $$ you’ll be saving on gas!
Check your tire pressure monthly at a time when the tires are cold. Before filling them, be sure to check the optimum pressure limits for your tires—it’s generally posted on the car door, glove compartment, or your car manual—and don’t over inflate the tires. If you are purchasing new tires, consider higher pressure limits and reinforcing. Radial tires get an average of 4% better mileage than bias-ply tires, so you could get an extra 12 miles out of a single tank of gas! (based on average 300 miles per tank)