Tire pressure gauge

my mechanic uses one of those cheap gauges. I bought myself a digital( Accutire) at costco. There is quite a difference between the 2- like maybe 5psi. I have become obsessed what with the new cars having that warning light.I like the mechanic otherwise but I really don’t trust that one thing. What should I do?

Check your tyre pressure yourself and don’t worry about what your mechanic has. However I would suggest that you may want to have your tyre pressure gauge checked and to make sure the tyre temperature is the same for both measurements.

Yep…What he said. Those cheap slide out gauges just are’nt accurate

Personally, I consider a dial type gage to be the most accurate. Most of them use an arced tube, called a “bourdon tube”, that straigtens as the pressure inside is increased, much the way a party favor unfurls, and moves the needle. They’re pretty stable and reliable.

I’ve been using a dial type gauge for the last 25 years with good results. Are you measuring the tire pressure at the same as the mechanic or driving home first? From experience, I’ve observed a 3 psi increase in pressure after the tires have warmed up from driving a few miles.

Ed B.

how do you verify the accuracy of a tire pressure gauge? I do check my tires execpt the spare on my Tacoma is physically inaccesible for me.

I have at least eight tire pressure gauges including one battery powered digital gauge, three pencil type gauges and the rest are bourden tube dial gauges including two that I paid about $15 for each but I still don’t know which is accurate. I tend to take a rough average of the most expensive and newest gauges and go with that as being correct or at least close enough for tire work.

Pencil gauges have a bad reputation. They can be accurate but I find it best to warm a pencil gauge in my hand for a few moments if the weather is cool.

The very best that you can do is to get your gauge checked at a scientific instrument calibration service; usually available in a larger city that has plenty of manufacturing, research or R & D going. It will cost you about $30 to $50 to have your gauge checked at a few strategic pressure readings where you will use it most.

Another thing that you can do for less than $100 is to buy a new bourden tube gage with a calibration certificate and fit the gauge with a tire chuck. These calibration certificates typically expire in one year.

Your daily use gauge need not be corrected; all you need to know is the error, if any, at a particular reading.

Anything else is just a guess.

Even nice ones are no more than half the price of half-decent digital tire gauges.

After using (and dropping) my 35 year old brass,rubber encased, dial type gauge I figured it couldn’t possibly be accurate any more so I bought a new decent digital gauge. They both read the same except the old one doesn’t read in 1/10 of a pound. But why would you care about tenths of a pound unless you were on a NASCAR crew?

With street tires, + or- 3 psi will not make enough difference to worry about…I consider $4.50 to be a high-end tire gauge…

I have sereral of the cheap ones and one better Harbor Freight Round Dial Gauge. I tend to rely on the better one that I got at harbor Freight. With all of the cheap ones I also tend to average also.