How To Check Tire Pressure and Inflate Tires

Edmunds.com

How To Check Tire Pressure and Inflate Tires

Avoid early tire wear, blowouts and bad fuel economy by checking your tire pressure every month. Here's the no-hassle way to get up to spec.

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a1cmugs2

I don't agree, The label on the door jam maybe at good reference but every manufacture of tires have different inflation.
Some tires have 45Lbs some have 32lbs and this varies by brand of tire.

You need to look at the tire and see what the tire pressure is cold.
The sticker on the door jam maybe for the tires that were on the vehicle at time of production but if most operators have replace there tires the brand of tire may have different cold pressure inflation.

jweebs86

You can also buy a good quality air compressor at most hardware stores and keep it in your garage, rather than buying a cheap portable one at an Auto Parts Store. This is a good way to go if you have several drivers in your home and want to check all of the cars at once.

jweebs86

In response to a1cmugs2: From my experience, the pressure ratings on tires are often the maximum pressures that the tires should ever be filled to. Even if a tire has a maximum pressure of 45 PSI, it doesn't mean that this is the best pressure for your car.

alvarezjacob

I'm cheap so I used an analog pressure gauge and a bike floor pump. Although it takes some effort to manually inflate the tire, after you do it a few times you can roughly calculate how many pumps it will take to raise the pressure 1 unit, which is pretty nice. Also, you get a decent workout when inflating all of your tires.

ajb999

Should the pressure be checked when the car is fully loaded to capacity or before it is fully loaded? Several hundred pounds added to the back of a minivan should increase the pressure reading versus unloaded. Will pressure be too high if filled to recommended level and then the load is put in?

carvel

If “cold” always meant the same temperature, and if the temp. inside tire shops was always “cold”, I’d be happy.
I phoned Goodyeare Tire Co. & asked the customer service rep., “If I inflated my car tires to 32 psi at zero degrees fahrenheit, and then heated them up to 100 degrees, what would be the pressure in the tires?” He replied, “That is a secret. I’ve heard that question before, and the answer is a secret.”
Personally, for each car I own, I make up a chart w/2 columns: Temp. & pressure. I assume that the cold temp. outside is ALWAYS zero. Then I write in pressures, w/ the top pressure being whatever is the “Maximum Pressure” on the tire’s sidewall. By filling in the remaining blank spaces, I can assume that the tire isn’t underinflated any day of the year.
Of course, all this presumes that car tires are designed to run safely at 44 psi at 100 degrees, etc.
I wish tire manufacturers would publish a “tire pressure safety margin” range of pressures for each temp. from zero to 100 or 115 degrees.
I forbid tire mechanics & oil change shops from checking pressure on my cars, so they won’t let air out.

Hoser7243

Don't people count or should I say add the 14.7 pressure we have in our atmosphere plus 35 pis = 49.7 p is ?

kyfdx

Hoser7243 said:

Don't people count or should I say add the 14.7 pressure we have in our atmosphere plus 35 pis = 49.7 p is ?

There is no atmosphere on the inside of the tire, which is where pressure is measured.

capriracer

Old thread and I'm hesitant to revive interest in a thread with so much misinformation, but it has already been commented on, so here goes:

Tires are standardized and a tire of a given size and load range has more or less the same load carrying capacity at a given pressure - so, NO!, it doesn't matter who the manufacturer is, the pressure listed on the vehicle tire placard (the label on the doorframe) is appropriate. Will tires from different manufacturers feel excatly the same? probably not, but that is more about how the manufacturer tunes the tire.

Tires are supposed to be inflated at ambient conditions. So the pressure for a wintery 40°F and a summery 100°F is the same. HOWEVER:

The rule of thumb is that tire pressure will chamge 1 psi for passenegr car tires (3%) for every10 °F change in ambient temperature. So if you inflate your tires to 30 psi at 100°F, then at 40°F, they will only have 24 psi.

And, YES!, the tire manufacturers include a margin of safety for their max pressures - meaning that you can exceed the max pressure when the tire is in operation and thoroughly warmed up (provided the operating conditions are appropriate).

texases

I agree. Some of the prior posts border on dangerous advice...

ralphhightower

I created an Excel spreadsheet from Weather Underground that has the daily high and low averages for my area and I average those daily numbers into a monthly average. For example, the monthly average of the average high and low temperatures for August for my area is 81°F. I try to check our cars tire pressures on a monthly basis when the outside temperature is near the monthly average before the cars have been driven anywhere.
I bought a great tire inflator from a tool manufacturer that can run off 110V AC, 12V DC cigarette lighter, or a 20V lithium-ion battery. Dial in the desired air pressure and it automagically shuts off when the pressure is reached. It does not deflate air pressure if it is higher than the desired pressure. I think that I'll use my auto store 12V cigarette lighter tire inflator and burn that up is there is a large volume of air to fill.