Do you trust a Pressure Gauge or TPMS reading more?

RobWNY

Senior Member
Joined
Apr 21, 2020
Posts
335
I filled all four of my RV tires using my Viair 400P using the included tire inflation gun w/gauge to 80 PSI. When my EEZTire TPMS connected to each tire pressure reading, they were a little different. The 4 tires read 74psi,76psi,77psi and 77psi. When I checked them with a certified ANSI accurate gauge, two tires read 78 PSI, one read 80 psi and one read 77 psi. So which readings should I trust? I realize a couple of psi one way or the other doesn't make that much difference but I'd like to have one gauge that I semi-trust.

Sorry I thought I was putting this in the regular General Discussion. Mods, please move this if you feel it should be someplace else.
 
Last edited:
I trust the gauge over the TPMS, but both are close - within 2 to 5% overall, much like the results you’ve found. My chuck has an ANSI certified 0-100 gauge and as my trailer tires are 65psi, it is a nice mid range on the dial. The gauge has been checked with others and is always close. The TPMS on my truck is a pound or two high on one tire. Not sure I’d worry about a 3% difference. It is the cold to hot difference that matters.
 
My use of a TPMS is to detect that the pressure is going down, when it shouldn't be. I'm not concerned about it being out a few percent compared to a calibrated gauge.
If I want accurate tire pressure numbers I will always use a gauge.
 
My use of a TPMS is to detect that the pressure is going down, when it shouldn't be. I'm not concerned about it being out a few percent compared to a calibrated gauge.
If I want accurate tire pressure numbers I will always use a gauge.

Agree completely, the use of a TPMS will let you know if a tire is losing pressure. another thing it will help to identify is when pressure increases substantially - usually means a tire is running hot.
 
Same experience here with at least 3 different brands of TPMS' over the years. The TPMS doesn't always match the tire pressure gauge readings.

Using a gauge I fill my tires to the same level I want on all 4 and find that the TMPS (currently a TireMinder I-10) is within 2 to 3 pounds of what I put in, and all 4 tires are within 1 PSI as shown on the TMPS.
 
I have a DeWalt inflator and if I set it to 81 psi the tires are at 80 psi. I have verified it with a gauge and my Tire Minder TM-77 TPMS. Every so often I will re-verify with a tire gauge.
 
Thanks everyone. I'll go with what my certified gauge says and call it good.
 
Don't worry too much over a few percent difference. You'll likely get that much between 2 gauges and the way (angle) you read them at if they are dial gauges.
 
My gauge is most trusted when standing still.... I that know one device is calibrated with itself vs tiny variations that might exist with four individual sensors.

I do trust my vehicle sensors more than I do an add-on system, because the truck's are tied into the ABS system that monitors each wheel's rotation. As pressure goes down in one tire, it starts to spin slightly faster.

Sent from my SM-G981U using Tapatalk
 

New posts

Try RV LIFE Pro Free for 7 Days

  • New Ad-Free experience on this RV LIFE Community.
  • Plan the best RV Safe travel with RV LIFE Trip Wizard.
  • Navigate with our RV Safe GPS mobile app.
  • and much more...
Try RV LIFE Pro Today
Back
Top Bottom