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Tire Pressure

My husband and I have an ongoing debate on tire pressure. I drive an 05 Ford Freestyle and inside the door it states that the tires should be at 32 psi. On the tires it says a max of 44 psi. My husband insists that it should be at 32 and that the pressure increases as I drive. My tires always look low to me and I often have people tell me to check my tires, especially my front ones. I am driving to Florida from Michigan in a few weeks and want to have my tires at the right psi.

tire pressure on side wall is the max pressure tire can be safely inflated…the door panel states what the pressure the tires for your vehicle should be. measure tire pressure when tire is cold.

Your husband is right. Follow the door. The 44 max is what the tire could handle - its just a “not to exceed” number, but that is not what you’re after.

The tires do heat up when you drive. When you leave Michigan, check them about mid-morning or so before driving. Put them at 32 or maybe a couple of pounds over.

When you get to Florida, check again. Given the warmer weather they will end up being overinflated.

You can’t tell whether a tire is properly inflated or not just by looking. You have to put a pressure gauge on it.

Hubby wins this one hands-down.

The tires on your vehicle may not be the origninal tires or the manufacturer’s recommended tires. Tire pressure will rise a bit on the road, but not from 32 to 44 psi.
The pressure on the tire is the cold pressure, what you should inflate it to at the air pump as close to your home as possible. The tire is built to compensate for the small changes that driving long distances will cause. For a more extensive discussion of tire pressure, go to the archives here. Be aware that rims are designed for specific tires as well, and figure into the equation of tire pressure.

Generally when a radial tire looks low, it is really really low on air pressure (like about 20lbs). Perhaps you should carry a tire pressure guage in the car and check the tire pressures during the trip. The pressure should be 32 when the car is cold, like in the morning before you start out. If you check the pressure at a rest stop when the car is warm from being on the highway the pressure would be closer to 35 or 36.

Over inflating a tire is just a dangerous as under inflating. If this is a debate, your husband is on the winning side of this one.

Maximum pressure is nice to know if the tires were on a pickup and you were hauling a load of wood in the back. Then you could have 44 PSI in the rear tires, although you probably wouldn’t need that much pressure unless the truck was really overloaded.

Consider it this way. If those numbers were reversed, it would mean you needed a new set of tyres to be safe.

BTW both of those numbers are for the tyres cold. If you have been driving for a while the pressure tends to go up, until it cools down. That is OK. You want to measure them when the tyres have cooled off, like in the morning.

Your husband is right, assuming the tires are the original size.

Well, I have to give this one to him. I’m normally the car person, so this is a big win on his part. Thanks for the info and I’ll check the tires. When we drove to Arizona 2 years ago, no problem, so I’m sure we’ll do great again.

Your husband is right, but use a digital or dial gauge. Don’t trust those pencil shaped gauges.

I agree with circuitsmith. Husband is right, but if your tires look low, check the pressure with a good gauge. I recommend a Meiser Accu-gage dial type (about 6 or 7 bucks at Sears). It’ll be the best $7 you ever spent.

In addition to the other good advice, just make sure you check the tires (with a good gauge) first thing in the morning, before any driving. That 32 psi number is for the tire when it’s ‘cold’, meaning before it’s heated up by driving. It will read higher than 32 psi after a drive, that’s OK. And radials tend to look a little low, that threw folks off when they first came out. Do your tires wear evenly? If they wear on the inside and outside edges more than the center, that would be a sign of under-inflated tires.