Tires: tires, tire placard, turaus

Question
my husband and i have a 2007 ford turaus.  What does 30psi means? and why does one tire more than other tires?

Answer
Katie,

30 psi mean 30 pounds per square inch - a measure of pressure.  That's the amount of pressure that is supposed to be in the tire.  If you have less than that, the tire is likely to fail.  More than that and the ride will be harsh.

BTW, that's "cold ", meaning before the tire has not been operated or after an hour and a half of idle time.


You should check your pressures once a month - oh, and pressure varies with temperature, so as summer comes on expect the pressure in your tire not to need adjustment, but when winter returns expect the tire to need air.

And tires on different vehicles need different pressures.

On every vehicle sold in the US, there is a sticker – commonly called the tire placard - that lists the original tire size and the proper pressure for that size.  The placard is usually located on a doorpost or in the glove box – but sometimes it is located in the trunk or on the fuel filler door.

Personally, I like a car that handles crisply. So I use 3 to 5 psi above the placard pressure.  I also get better fuel economy, better wet traction, better snow traction, better tire durability, better tire wear, but I do have a degradation in ride harshness (but I am willing to put up with it.)

BTW, it doesn't matter who makes the tire or what pressure is listed on the tire's sidewall, if the tire size is the same as the placard, then the pressure listed on placard is also appropriate.