Fuel Economy Tip - Proper Tire Pressure
April 21st, 2006 | by Brian Carr |Most people tend to care about their tires’ air pressure when the tire goes flat. However, properly inflated tires can help you increase your car or truck’s fuel economy.
Make sure that your vehicle’s tires are properly inflated.
According to AAA, driving with under inflated tires can reduce your vehicle’s gas mileage and fuel efficiency by up to 2% which, for a $3.00 gallon of gas, causes you to lose $.06 per gallon.
The reason under inflated tires reduce gas mileage is because they are less “round” than properly inflated tires. Due to being less round, under inflated tires require more energy to begin moving and to maintain speed.
I like to check my vehicle’s tire pressure at least once a month, usually when I’m already at a gas station, so that if I have to add any air, I can go ahead and use the gas station’s air pump.
You should be able to find the proper tire pressure in your vehicle’s owner’s manual. If you can’t find it there, check on the driver’s side door.
11 Responses to “Fuel Economy Tip - Proper Tire Pressure”
By Anonymous on Apr 22, 2006 | Reply
Great tips!!! As always, your dedication to every venture you pursue shows in this site!!!
Tricia
By Anonymous on Apr 22, 2006 | Reply
Are you going to add a link so that I can subscribe to this site???
By Goten2 on May 4, 2006 | Reply
This is wrong. You need to check your tire pressure when it’s cold. As you run the car, the tires get hot and the pressure inside your tires increase. So, if you check your pressure at the pump (I’m assuming at this time your tire is already increases by about 1 or 2 psi), then when you fill/deflate to the recommended tire pressure (which you look at the driver side inside wall) it’s actually less than the recommended.
This is important because if you don’t check the pressure at cold tire, you’re most likely underinflating your tire; therefore, loosing mpg.
By Brian Carr on May 4, 2006 | Reply
I haven’t seen anything regarding the PSI increase, but assuming that’s true, most people don’t have an air compressor at home, and it’s probably best to check the tire pressure just before you add air.
I don’t know how long it takes a tire to warm up enough to increase the PSI by 1 or 2 pounds, but if you go straight from home, work, etc. to the station to add air, I would assume the pressure wouldn’t have increased enough to cause a misread.
By Goten2 on May 10, 2006 | Reply
Here is an excerpt from my car’s manual:
Caution: Always observe the following:
Check pressures when the tires are cold. That is, after the car has been parked for at least three hours and hasn’t been driven more than one mile or 1.6km since starting up.
Checking the pressure when the tire is cold is also recommended by cars.com (http://www.cars.com/carsapp/national/?szc=60657&srv=parser&act=display&tf=/advice/caradviser/tire_pressure.tmpl)
Hope this helps people since “lower-than-recommended tire pressures cause uneven tread wear and poor handling.” (2004 Elantra Owner’s Manual)
By Brian Carr on May 17, 2006 | Reply
Thanks for the update regarding when to check your tire pressure. Hopefully people will see this and remember to check their tire pressure BEFORE heading to the air pump.
By Anonymous on Jul 21, 2006 | Reply
While it is true that the correct air pressure for the stock tires of your vehicle can be found either in the owners manual or inside the door, replacement tires may call for different pressure. I recently replaced my tires, and the new ones call for 12 PSI more than the old ones. Check the sidewall of your new tires or with your dealer.
By Jimmy on Jun 6, 2007 | Reply
I have a used 1991 Chev. Lumina with P195/75R 14.92S M+S tires. I can’t read the placard–it is completely faded out. What is the proper inflation? Does M+S stand for mud and snow? I doubt it, the car was purchased in the San Francisco Bay Area originally. They don’t look like mud and snow tires. I recently replaced one of the tires. The tire shop inflated the tire to 35psi. Should I inflate all the tires to 35psi? The rest of them are between 30 and 34. In general, is there a web site that has a table of tire inflation pressures for various tires and vehicles?
By Brian Carr on Jun 7, 2007 | Reply
Jimmy - to be perfectly honest, I’m not sure what to tell you. I’d check and see what it says in the owner’s manual to find what the car’s manufacturer recommends.
By Rob on Jun 17, 2007 | Reply
Brian, it doesn’t take very long for the tires to heat up, especially when they are low. To solve the problem of not having a compressor available at the house, just measure the pressure when they’re cold and note how many p.s.i. are needed. Then at the station, read the pressure, add as many pounds as you noted. By the way, the lower they are, the more quickly they will heat and the hotter they will get. This is one of the reasons that underpressure reduces gas mileage. The tires flex much more, thereby absorbing energy and producing heat. It’s also true that it’s equivalent to continuously going up a small hill when they are underinflated.