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Discussion Starter #1
What is the tolerance on these things before the warning light comes on? My light is on and 1 tire is 1 lb less than the other three. Are they normally this sensitive? Cold pressure this morning was 29 on three, 28 on the RF.
 

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It might be temperature-related. It's wierd, yeah, but I ran 35Lbs in mine for the winter, but soon as summer hit, the TPI came on until I bumped them all up to 40PSI.

!c
 

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Discussion Starter #3
Mine did go off when it got around 100 yesterday. I'm using a pretty good dial pressure guage, so I think I'm getting a good reading. 1 lb. difference is pretty close, maybe it's saying they are all too low?
 

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TPMS should only activate if the tires are below 30lbs.. which by your readings are.. there is your issue.

I wish somebody could make a cheap TPMS that activates at a lower pressure..
 
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By my gauge (and there all different it seems) I need about 36 PSI to stop the darn thing from coming on. Mine are very sensitive also.
 

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Discussion Starter #10
Tried to air em up yesterday afternoon. The side in the sun (it was about 100 here) was 5 lbs higher than the shady side, after sitting for a couple of hours. Waited til this morning and aired em up to 35.
 

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My girlfriend's Dodge Dakota (2008) will activate the TPMS when low temps cause the tires to loose only 1- 2 lbs of air. I removed mine along with the stock wheels, and the jeep doesnt seem to care. Once in a while the light will come on if I am going on a long hwy trek, but it seems to "cycle" back off after another 60 miles or so. Then when running around town or for shorter hwy trips (20- 30 miles) it never comes on again. Keep in mind that these things (x5) are not cheap to replace and they are a direct part of the valve stem assembly...so if using them, be careful of damaging them (like on rocks, etc...), and throw away your Fix-a-flat...cause that stuff will clog them completely.
 

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X2 on the not cheap. (So lets just say I shot myself in the foot with an aftermarket TPMS system).

I am a fan of systems monitoring. After having a number of flat tires on my 2001 Durango I started looking into after market TPMS systems and bought one for my 2007 JK. I had three sensors (including the warranty replacement sensor) fail in 21 months. So I replaced the whole system with a Hella brand and we'll see how this one goes.

So replacement costs for the aftermarket sensors are $50 each or so. The sensor batteries are 'supposed' to last 5 years (I had one go low battery after 21 months). Mine were 'supposed' to be accurate to +/- 2psi. Even balancing all five tires to the same pressure I couldn't get two sensors to indicate anywhere close to what was on the gauge. One was stuck at 37psi (a second failed sensor) and another read 4lbs low. I also had one sensor that was stuck at 137 degrees (the third failed sensor). When another sensor went battery low, I chucked the whole system and got the Hella.

So anyone want a slightly used TPMS system to experiment with? I'll sell you my replaced TRIKOR system cheap.
 

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Not sure how you are still a fan of those things. I miss the days when you could simply walk around the vehicle every once in a while and use those things called "eyes" to tell if a tire was low. Or use that neat space-age techno wizardry apparatus known as a "tire gauge" (!) Man...those were the days. I think we can all thank Ford and Firestone for this.

BTW- $50 is cheap by some standards...Ive seen TPMS that run up around $70- $80 each!
 

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Yeah, I do the walk around also. But it has been my experience that I pick up a nail while driving around, not walking around. And Murphy will most always pick the right time for him to set the tire flat. Like that time I took a backroad shortcut over to Ouray and had some women flag me down to tell me I had a flat tire. I had so many flats with that Durango. Out of five tires, four had been patched, some multiple times, and one poor tire had three.

Sad thing is, most people DON'T use their eyeballs and have no clue they have a low tire. I drive a lot, and few days go by that I don't spot some idiot with a half-flat tire cruising the streets. THAT is the reason (and not a few lawsuits over failed under inflated tires) that caused the tire industry to lobby congress for the TPMS.

So am I still a fan of TPMS? Yes. Just not the TRIKOR provider. If it had not been for poor quality control and multiple failed sensors I'd still be using it. But having four out of six (the warranty replacement failed) sensors fail in less than two years I wouldn't buy that brand again. They have a great concept in display and progammability, but poor sourcing in practice.

And the expense? I think having to buy battery powered sensors where the purchaser has no clue how long the replacement device has been on the shelf is a failure of Congress. The battery industry was forced to put dating on their batteries and I think forcing the TPMS industry to do the same would be wise. And having a five year suggested life just forces the second owner to invest another $300 to replace sensors (sensor cost plus installation). THAT sux. So what'll happen now is yet another law that puts TPMS check as part of the safety inspection (as emissions, lights, horn, brakes, tread depth) already is. The local NTB told me they get $48! to reprogram a customer's TPMS if the customer doesn't know how to do it.

So, sorry for the soapbox. I know my next vehicle will have it and I'll take it up the * like everybody else who purchases a new vehicle in the U.S. My thanks to all those people who blamed the tire manufacurers (alright, FIRESTONE deserved the lawsuits) for failing to check their tire pressures periodically. :pissed:
 

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Good post...But the issue that I was referring to about Firestone that I believe put all of this overbearing safety crap in motion was when all those SUVs were involved in roll-over accidents. But it (I didnt think) had anything to do with under-inflated tires , rather an issue with materials or manufacturing defects that caused the sidewalls or tread to seperate or prematurely wear and cause subsequent blowouts. I really may be wrong about how I am remembering that whole deal...but I know that Ford and Firestone fought like cats and dogs over whose liability it was. So again, law makers, etc just ran with the ball on the safety improvements that were needed to protect joe public. In the future, I predict that lights and audible indicators will be a part of every car and tell us things like..."left front sidewall is dirty/ Please clean windshield/ You need to shower today/ Your a$$ stinks..." That sh!t will never end....as long as insurance companys and law makers feel there will be fewer law suits, claims, etc...Sorry, but the jk is testament to too many indicators getting in the way of each other and the computer not being able to tell what the hell is going on. I'm sure that some of it has to do with the off road functions not being able to overide the safety features....but how many computer generated babysitters do we really need?
 

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Hey! I should tell you about my Firestone 7-2-1 tires I had on my 1975 Mustang II. Or their replacements, the Firestone 500 tires. Both of them subjected to recall. Those are the reasons I'll never (if I can help it) buy another Firestone tire. The first set of tires I replaced two before the recall and had two replaced by the recall. The second set I had all four replaced.

And the rollovers? I think you are right. (just another reason for me not to ever buy another Firestone tire). My lawyer friend was involved in one of those lawsuits. He still has that Explorer involved in the rollover parked in his son's back lot. Seeing that vehicle makes me glad there is somewhat of a rollcage in the JK. (alright, I admit I have a friend who is a lawyer. So sue me. That's a joke. I also have a bother-in-law who is one. Better yet, sue him. My sister could use the money.) Heh.
 

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TPMS should only activate if the tires are below 30lbs.. which by your readings are.. there is your issue.

I wish somebody could make a cheap TPMS that activates at a lower pressure..
You can take your Jeep to your dealer and have the sensors flashed to a lower pressure.
 

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i have heard this but i do not htink it is enough to make a difference for offroading.
 

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My tire pressure monitor light just came on tonight and its one of the first cold nights we have had and I'm thinking it may be temperature related because I checked my tires and they look fine.:bounce:
 

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Discussion Starter #20
They're back...... dash indicator has been going off for a few days, off and on depending on the temp.. freezing Friday morning, high 80's Saturday.. checked all tires this faternoon, lowest was 31... aired em all to 35.. yes, spare was fine, indicator STILL going off... these things are a pain..
 
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