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Tire Pressure Warning Light

Personally for an inflator, I would get something like this little guy:

http://www.menards.com/main/tools-hardware/power-tools/compressors-and-pneumatic-tools/compressors/tool-shop-2-gallon-air-compressor-with-2-pc-accessory-kit/p-1442765.htm

Why? Because those ones that plug into the cigarette lighter won’t fill the tires as fast. And because you want to be inflating your tires in the morning after the car’s been sitting overnight (because after you drive on them they heat up, which increases the pressure, and the psi rating on the door frame is cold psi). So since you’re inflating them in the morning before you drive, you’re home anyway, so the cigarette lighter inflator isn’t necessary.

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What you say is true, but I want an inflator that I can carry in the car in case I also need to use it away from home. Hence, the one that I bought.

There’s a Car Talk tire pressure monitor for sale through the NPR site… might make someone a nice gift!

http://shop.npr.org/programs/car-talk-shameless-commerce/car-talk-analog-dial-tire-gauge

+1 to ccatx’s find.
That gauge looks very much like the one that I bought from Brookstone–about 25 years ago, when they still sold tools instead of yuppie toys. In fact, in addition to the Brookstone logo, the face of my gauge also displays the Accu-Gage name, so I tend to think that it is very similar–if not identical–to the one I own.

The gauge still works flawlessly after all those years. By comparison, a friend of mine bought a Slime brand gauge a few years ago, and it was broken after less than 2 months.

One other thing I should mention if you live in an area that has large temperature swings the Toyota scan tool has the ability to calcute pressures based on reccomend pressure and ambient temperatures. There are also charts that use can use like the one in this article http://www.brakeandfrontend.com/getting-accurate-toyota-tire-pressure/

Shadowfax read my mind. For $50-60 you can just get a little compressor that can also do other light jobs like blow things off, run a staple gun, air brush etc.

Late October/early November my TPMS illuminated. I checked pressure and with the 20 degrees temperature drop (60s to 40s) all tires were down from 32psi to 30psi which is perfectly normal. I drove 2 miles at 35mph or less to my trusted tire shop and they (at no charge) increased pressure to 34psi. Temperature is now in the 20s without TPMS illumination and pressure is 32psi. It appears the 1psi pressure drop for a 10 degree temperature drop is accurate.

And just so everyone understands:

Tire wear is relatively insensitive to inflation pressure. There are other things that are much more likely to cause tire wear issues. Small differences in tire pressures (up to 5 psi), do not appreciably change the wear pattern.

So you don’t need to be overly concerned about trying to follow the daily/weekly/monthly cycle of temperatures. Set your tire pressures for the worst case (the coldest likely temperature), and be confident that they will be fine for everything else.

It doesn’t have to be spot on, no, but especially with the low profile tires that are coming on almost everything, tires themselves are more sensitive to pressure changes. Drop 10psi on the tire from an old 80’s Crown Vic and it won’t be nearly as noticeable as dropping 10psi on a new car wtih tiny-profile tires.