On the way to work this morning, my low tire pressure warning appeared. I stopped and checked the pressure in all my tires. Three ranged from 38-40 psi and one was at 26 psi. My tires weren't cold, but I had only been driving for about 15 minutes. Shouldn't the pressure be closer to the recommended 33 psi?

BTW, My mileage has been just over 40 mpg in my first 1,200 miles.

 

You'd have to know your tire temperature to guess if they're overinflated. A tire inflated to 32 psi cold can hit 40 psi under normal conditions. It's much easier to just measure the cold tire pressure and check that vs what the door tag (or wherever it is in the FFH) says it should be.

Using the rule of thumb of 1 psi per 10 deg F, it looks like you have 3 tires a tad overinflated and 1 tire very underinflated, and/or your pressure gauge is bad.

 

It sounds like you have a slow leak in that 26 psi tire and I would get it looked at and fixed right away. The TPM system just paid for itself and could have prevented an accident.

My first '05 FEH came from the factory with 40 psi also and I thought is was the warmer weather here in So. FL that raised the pressure. The max rating on the sidewall is 44 psi on my tires and that's what I set them at. A few months later I was doing some coasting test and raised the pressure to 50 psi. I kept the tires at 50 psi and have noticed better MPG, wear, handling and less chance of hydroplaning. Read This:
http://www.cleanmpg.com/forums/archi...p/t-11652.html

What ever you choose to set your tires at, don't go under what's posted on the driver's door.

GaryG