Tire air Pressure

[Ole Anderson]

Am I correct that TPMS are required on all new cars now? Wife's 2009 Vibe only alerts when a tire (you have to figure out which) is under inflated, I think it goes off at 25% low (26 psi) on a 35 psi normal tire. My 2015 GMC Acadia will send me an email monthly (via Onstar) with all sorts of parameters including tire pressure, and what needs attending to. It cautions to adjust tire pressure if it below 32 psi IIRC. Also miles to next oil change. Of course a low tire (25% low by law I believe) will alert on the dash. Having to check tire pressure on a late model car is a thing of the past.

[Myk Rian]

I check them with the season changes. I also fine tune the pressures for the best ride and handling.
If tires need air every couple weeks, check the valve stems for leaks around the hole in the wheel. Corrosion does happen there.

[Jim Becker]

The pressure monitoring system in my wife's car is on the helpful side. It shows individual tire pressures, but there is no indication which pressure goes with which tire.

I consider its reading as telling me to check all tires manually. Then again if I had gotten the air stuff out I would have checked them all anyhow.

Strange that the display doesn't portray the location for each reading...our vehicles do that.

[Rod Sheridan]

I check tire pressure monthly on the minivan, every couple of weeks on the motorcycle...........Rod.

[Bruce Page]

The pressure monitoring system in my wife's car is on the helpful side. It shows individual tire pressures, but there is no indication which pressure goes with which tire.

My cars display is the same way, it gives PSI for each tire but no correlation to which tire. I have figured out which is which through trial & error. It has never made any sense to me why they did it that way. My wife's 2012 car is even worse, it'll give you a low pressure warning if a tire is low but that's it - no psi numbers or which tire is low. Both cars are Infiniti brand SUV's

[John K Jordan]

My cars display is the same way, it gives PSI for each tire but no correlation to which tire. I have figured out which is which through trial & error. It has never made any sense to me why they did it that way. My wife's 2012 car is even worse, it'll give you a low pressure warning if a tire is low but that's it - no psi numbers or which tire is low. Both cars are Infiniti brand SUV's

Maybe the software guys are getting smarter. My wife's Murano, a couple of years old, is like yours but my 2017 Jeep shows which tire has which pressure. Or maybe just slowly release features to encourage dissatisfaction with last year's models. Next will be the the automatic inflation system in use on larger vehicles for years.



JKJ

[Ken Combs]

Maybe the software guys are getting smarter. My wife's Murano, a couple of years old, is like yours but my 2017 Jeep shows which tire has which pressure. Or maybe just slowly release features to encourage dissatisfaction with last year's models. Next will be the the automatic inflation system in use on larger vehicles for years.



JKJ

The more info the systems display, the more complex maintenance becomes. If the pressure is displayed by position, tire rotation must include a 'relearn' process that requires a special tool.

Owner maintenance is effectively prevented. And, any business, other than a brand dealer, that wishes to do tire maintenance must invest in the tool. Of course, that cost is ultimately passed on to all customers, not just those driving brand 'x'.

My Tundra and Town & Country, both display a warning of low pressure, but no position info. that is fine with me, as I can move tires, change tires etc without having to provide the computer system with an added info.

All conveniences have an associated cost.

[Yonak Hawkins]

I have three gauges, all of which indicate a different pressure. How do I calibrate or verify what is the correct pressure ?

[John K Jordan]

I have three gauges, all of which indicate a different pressure. How do I calibrate or verify what is the correct pressure ?

Ha, the age-old question of any instrument. ("The man who has one clock always knows what time it is; the man who has two is never sure.")

I have found horribly poorly calibrated pressure gauges, dial, stick and digital. (Digital were the worst I've had) There are companies that will calibrate anything but it costs money. Do it yourself? My first thought was to use a water column but wasn't sure about the best way to go about it. So Google gave me this: http://www.carsdirect.com/car-repair...pressure-gauge A bit of an effort!

I know you can purchase calibrated master gauges but I suspect they are expensive. (a good tire shop may have one and be willing to check your gauges - especially if you are a customer!)

I have a pile of pressure gauges, some cheap and some expensive and supposed to be high quality. One way to check: Compare them all, write down the readings, and throw out those furthest from the average.

This is impossible with some gauges I use, such as those with widely different scales such as the low-pressure gauges for the ATVs and those for my truck which needs 80 psi (for heavy loads). I just buy the best quality I can find and read and try to filter the ratings.

This Consumer Report rated a couple models higher. http://www.consumerreports.org/cro/t...ying-guide.htm

JKJ

[Yonak Hawkins]

Thanks for the thoughtful response, John, and the link to the Consumer Report ratings. I don't think I'll test using the CarsDirect method.

[richard b miller]

if checking air pressure in tires is so important, how come they make the psi text soooo small?

[Curt Harms]

My 2017 Fusion reads actual PSI First car I've had with that.

When checking pressure I'm partial to these gauges: http://www.ghmeiser.com/ (No idea if I'm related.)

I'd read that dial gauges are more consistent than the common 'stick' types. I have one gauge on a regulator that is filled with some sort of clear oil so the mechanism shouldn't get sticky with age. The electronic types are interesting (Ooooo, another gadget!!) but yet another battery to go flat at the most inopportune time.

[Curt Harms]

I have three gauges, all of which indicate a different pressure. How do I calibrate or verify what is the correct pressure ?

Maybe after having tires serviced by a reputable shop, ask what pressure they're inflated to then check with your own gauge? See how far apart the readings are? There'd be no guarantee but you'd hope a professional tire shop would have accurate gauges.

[Bert Kemp]

Last time I took the bike into DT they checked my tire with the gauge thats hooked to the air hose and he said I had 53 lbs in the back tire. I asked him to check it with another gauge because I knew I didn't have 53 in that tire , he got a dial one from one of the guys and it read 33, much better then he put the hose one back on and checked it at 33 he miss read the pressure DUH. But what happens when Granma comes in and the kid misreads. LOL

[Tom Stenzel]

I remember some of the GM systems used the ABS rotation sensors to monitor the tire pressure. If one tire spun at a different RPM while driving it was assumed one of the tires was mis-inflated. GM pushed to have that accepted as it used no additional sensors, required only a minor software update to the existing computer, and program one more message in the display system. I think it ended up the highway dept disallowed it as four mis-inflated tires would read as just fine.

When we went shopping for a used car for my daughter there were many cars with the tire monitor system in fault. A sensor would break or a wheel would be changed and the owners just ignored the light. Depending on the price of repair I might be inclined to ignore it too.

-Tom