tire inflation monitors

[Ryan Baker]

I have a question about the tire inflation monitoring system I have my factory tires on my truck its a 2009 limited with 18" mich. thetires state 44 psi max and are filled to 35 psi thats what the door panel says they should be at.... I keep them at 38 to 40 psi find the truck drives better, Today I noticed that my two front tires looked low so after checking they were both at 27 psi, my question is what is the set point at which the light on the dash will come on i feel that anything under 30 psi is to low and will cause the tires to wear poorly is there a way to set the point at which the light will come on also is there a way to test the system to see if all tires monitors are working correctly and will set the light off at that pressure with out deflating each tire.....



thanks

Baker

 

[Robert Caffyn]

Hmmm, dunno. I know mine work and the system has gone off. It might be based on how rapidly you lose air or at an actual PSI. Google tire pressure sensors and see what you find. BC

 

[EddieS'04]

My ex's '08 escape says 30psi on the door. Her TPS alert didnt go off until, one of her tires was at 15psi. That could have been a highway blowout. Go figure. I think the government forced junk science on us. I have heard simular stories.

 

[John Z]

I think the government forced junk science on us.

Not our government, they are so trusting and honest!:rofl:

 

[Scott Doughtie]

Under 25 psi....happened to me once after picking up a screw in the right front tire.

 

[Korey Kreiter]

If all your tires are low, it will not go off. 1 tire has to be a certain percentage (can't remember exactly how much %?) lower than the rest. You need to check them 1/month. PSI fluctuates greatly based on temp, etc. Use what the OEM door sticker says, not what the max PSI says on the tire.

 

[Dingo]

Right. It looks for a difference between tires, not a fixed pressure amount. I run mine at 37, but mine are almost 2" wider than stock.

 

[chargedtrac]

fyi...from www.tireindustry.org:

looks like there should be a 25% threshold



Tire Pressure Monitoring Systems

NHTSA published the third attempt at a TPMS Final Rule on Thursday, April 7, 2005. The news isn't good. NHTSA did not take TIA comments into account on behalf of the tire industry. The trigger threshold is still 25% underinflation. AND if that's not bad enough, NHTSA moved backwards on the timing of the trigger. Originally the dashboard indicator had to light up within 10 minutes of sensing an underinflated tire. In this latest version of the final rule, the telltale doesn't have to illuminate for 20 minutes. The phase-in has changed slightly: 20% of all new cars must comply by Sept. 1 of 2005, 70% by Sept. 1, 2006 and 100% by Sept.1 of 2007.



Another interesting site on TPMS is fordtpms.com.