What type of tire gauge gives the most accurate pressure readings?

Dear Car Talk | Jun 01, 2005
Dear Tom and Ray:
I have three different tire gauges, all of which give me different readings. They are all the old-style "pencil type" gauges, and all are made in China, if that makes a difference. How do I find one that can be trusted? -- Jerry
RAY: Well, the pencil-type tire gauges, with the pop-up plastic readouts, are notoriously inaccurate. You could buy five more of them, and you'd probably get eight different readings.
TOM: And the dial-up gauges used on air pumps at gas stations are even worse. You set it for 32 psi, you hear "ding-ding, ding-ding, ding-ding," and you drive away with 80 pounds of air in your tires, with your head bouncing off the ceiling.
RAY: We use a very precise dial gauge at the garage that cost us about 100 bucks, and it's a beautiful instrument. We keep it under lock and key, because if we didn't, my brother would use it as a hammer to free up stuck brake calipers, or to crack chestnuts.
TOM: But I'll tell you what. We got some samples of some inexpensive, battery-powered plastic gauges with digital readouts. Surprisingly, they were extremely accurate. You can get them at almost any auto-parts store now. They cost 15 or 20 bucks, and they use replaceable batteries.
RAY: Yeah. The batteries cost 14 bucks.
TOM: Nah, they're watch batteries; 3 or 4 bucks a pop. In any case, whoever makes these gauges (and I'm sure at least some of them are made in China), this style seems to be far more accurate than pencil-style gauges. So, that's what we'd recommend for you, Jerry.