Checking Tire Pressure

kinda like a vehicle's SOH

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Taoshum,

What's a SOH?

ArdraF

State of Health. I think that state is located near Indiana.

It's not a pacemaker - nothing in my vehicle is critically dependent on the TPMS working. Besides, it has built in diagnostics of some sort, so there is at least a rudimentary check on its health.

I think you are making a mountain of a mole hill, taoshum. If the TPMS fails, at worst I don't get the warning that I would not have had if I had no TPMS in the first place. And if I use the TPMS display to show tire pressure and it doesn't display, I know it isn't working. Even a false alarm is no more than in inconvenience.

Now, what about your manual tire gauge? Do you have that re-calibrated every 6 months? The typical tire gauge is notoriously inaccurate in the first place, and after knocking around for a year or two, who knows? And how about your eyesight and the little numbers on the gauge? We could make a terrifying story of the potential screw-ups of manual gauges and measures too, but it serves no good purpose. We use the tools we have, to the best of our ability, and get on with life.

the OP said:

OK, confession time. I've been trying to figure out a way to get into a whole lot of raging/ranting, real trouble on RVForum. I think I found a way! I came up with the idea for this thread. 

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It's not a pacemaker - nothing in my vehicle is critically dependent on the TPMS working.

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If the TPMS doesn't provide critical safety information, why have it?  If it tells you everything is "fine" but if it is not, it may well lull you into a false sense of security... molehill or mountain... all depends on your perspective. 

In any event the OP seems to have been successful... LOL.

When I replace my tires this fall I will have the DuallyValve metal extensions installed. They come with a rubber stabilizer that its in the wheel hole to stabilize them. With the tires off the rim there won't be a charge to install them.
You can see them here http://www.borgtiresupply.com/index-dv.htm

Gee, I guess I'm crazy, I have the stainless-steel braided hoses, am I the only one that use them, they have a mounting bracket that goes under one of the lug nuts, have had them 5 yrs, when I put the tires on, also my tires have 95 psi, and  I add air seldom.

taxpayer said:

Gee, I guess I'm crazy, I have the stainless-steel braided hoses, am I the only one that use them, they have a mounting bracket that goes under one of the lug nuts, have had them 5 yrs, when I put the tires on, also my tires have 95 psi, and  I add air seldom.

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I guess I'm loco tambien...when I went to the FMCA thing in Farmington, I bought, like 6 tire valve extentions of various shapes and bends so that I could more easily check/fill/adjust the tire pressure if needed.  I've looked at 'em several times and checked the pressure a few times with the same gage for a year now and the pressure doesn't vary a bit as far as I can tell.  Seems to me, once the tire is on the wheel and inflated it gets pretty stable... these are the same tires that run on the gillions of big trucks, for hundreds of thousands of miles with several retreads.  I'm all the way to 12,000 on the original tire.  Now motorcycle tires... that's a whole different story.  But, I don't know, obviously.

taxpayer said:

Gee, I guess I'm crazy, I have the stainless-steel braided hoses, am I the only one that use them

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Add me to the crazy list.    I have braided extensions on inner rear wheels too, and a J-curve extension on one of the outer rears that has a valve stem that can't be otherwise reached even with a dual-head air chuck.  My RV tires hold air better than any of my cars, tow dolly, lawnmower, bikes, or wheelbarrow that I have.  That's everything I could think of that I am always having to check air pressure on!  I think the issue with the braided extensions is that they are more prone to failure and eventual air leaking, not that they leak by default.  If you check your tires often and KNOW they don't leak (like we've all mentioned), then if it does start losing air without explanation you can probably bet on the extension being the culprit.

Whatever happened to the "thud" test.
Check the pressure before a trip, do a test "thud" on each to learn the sound, then do it each time you get ready to leave a camp site, even if it is at Walmart. Have a big wrench (fits big nut on trailer hitch)--makes a good "thudder". A low tire gives itself away--although I've not found one yet. Tweedy

"Thud test" probably works, but I prefer a tire gauge.  Mine has a nice numerical readout, and just a little more accurate than a big wrench I'd guess. 

The "thud-test" is as accurate, as a string and 2 soup cans to talk on the phone.  Talk about ancient technology.  How can anyone tell the difference between 33 PSI and 28 PSI from slapping a stick on a tire?  The only people that I know that still do this are truckers, for which, they have a reason:

1.  Access to all 18 wheels of a truck is cumbersome.  Especially, for our truckers that drive overnight, and lighting conditions are poor.

2.  Time is money for the most part.  To take a tire gauge to each tire (daylight, and accessability permitting) just takes too much time.

For our RV's, there's NO reason why a billy club needs to be swatted at our tires.  None. 

As far as TPMS sensor systems go, for the most part they're pretty accurate.  Just like any piece of equipment, there is ALWAYS a chance for something to malfunction.  Doesn't matter if it's electronic or mechanical.  For the most part, false readings are user error.  Everyone knows (or should know) that air PSI drops in tires when temperature falls.  I remember reading somewhere that a tire will lose 1psi for every 10 deg drop in temp.  Using that theory, I can only imagine how many PSI a tire can lose from heating up while in motion, on top of outside ambient temp.  A tire can cool drastically after sitting from traveling for a couple of hours, then drop even more after sitting overnight due to outside temps.

The problem with this is most everyone I know DOES NOT check & adjust tire PSI on a cold tire.  If a tire with TPMS is checked and adjusted hot at 30PSI (for example) guess what?  In the morning, you better believe that TPMS sensor is going to blink or buzz to let you know that your PSI is below spec. 

Taoshum, no offense, but it sounds like you're more worried about the "what-if's" than the "what can it do for me" attitude, which sounds just a tad like the glass is half empty.  I mean, "what-if" a plane crashed into my house?  For the "most" part, most electronics have had plenty of research and design taken accounted for.  Yes, there are a lot of junk items out there.  But, it's preventable.  There's a TON of information on the internet from real live people that post their findings on the items they consume everyday.  Rest assured, if I need to research something, or find a review on something, I have no problem doing so. 

This is only my 5th season as a RV'er but I'm going to chime in on this discussion.  Retired Navy pilot, retired Continental Airlines Captain, last airplane flown was the B767-400. 

I have the Pressure Pro system installed on my coach (2007 Fleetwood Excursion) and my towed vehicle.  I check the tire pressures daily and at rest stops during the day.  I have seen what damage can occur when a tire comes apart.  Airplanes are much sturdier than a MH and blown tires can ruin your day.  The Concorde crash in Paris a few years ago comes to mind (no survivors).  A tire on a MV that comes apart at even moderate speeds has the potential to be lethal to not only the coach occupants but other vehicles.  I visually inspect the tires every morning before departure.  This takes me, maybe 5 minutes max.  It is worth it to me as it helps protect my DW and 2 cats.    In my short RV career the TPMS has alerted me to 2 instances of nails in my towed vehicle.  It has also given me several false alerts.  I take those seriously and pull over and check them out as they occur.

How many of you monitor your blood pressure and get false readings.  What is better, no alerts or driving around with no safety system.

Off my soap box.

Don

Don Jensen said:

This is only my 5th season as a RV'er but I'm going to chime in on this discussion.  Retired Navy pilot, retired Continental Airlines Captain, last airplane flown was the B767-400. 

I have the Pressure Pro system installed on my coach (2007 Fleetwood Excursion) and my towed vehicle.  I check the tire pressures daily and at rest stops during the day.  I have seen what damage can occur when a tire comes apart.  Airplanes are much sturdier than a MH and blown tires can ruin your day.  The Concorde crash in Paris a few years ago comes to mind (no survivors).  A tire on a MV that comes apart at even moderate speeds has the potential to be lethal to not only the coach occupants but other vehicles.  I visually inspect the tires every morning before departure.  This takes me, maybe 5 minutes max.  It is worth it to me as it helps protect my DW and 2 cats.    In my short RV career the TPMS has alerted me to 2 instances of nails in my towed vehicle.  It has also given me several false alerts.  I take those seriously and pull over and check them out as they occur.

How many of you monitor your blood pressure and get false readings.  What is better, no alerts or driving around with no safety system.

Off my soap box.

Don

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Very good points that you bring up.  I'd also like to add that a TPMS is not a replacement for visually checking your tires and pressure.  It's a system designed to alert you of something not normal.  And besides, all the checking in the world before hand will not do anything for the nail (such as you said in your example) getting driven in the tire while in motion. 

Next question (just for fun ), how many of you VISUALLY check your fuel tank before a trip, or...rely on the fuel gauge?  8)

I know I'm a minority opinion, but I have to agree with Toashum when it comes to relying on a "gadget" to monitor tire condition. Had a blow-out on an inner dual this spring and my TPMS merrily showed good for 250 miles of travel until a passing motorist flagged me down and informed me tread was coming off the tire. Turns out I had worn out batteries in the sensor (the unit is supposed to alarm that and didn't) and somehow the unit failed to pick up the loss of pressure. They can fail! My best advice........don't rely soley on a TPMS.

Depends on the TPMS. With PPro, if the sensor doesn't check in periodically, the main (dash) unit alarms. There's no question that it alerts you to a lost signal from the sensor, irrespective of the cause (low battery or just lost signal).

No disagreement about relying solely on a TPMS, but it's a lot easier than trying to continually take the tire pressures as I'm driving down the highway.

FWIW I check the tire pressures with a regular gauge before screwing the sensors on at the beginning of every trip, and again periodically during a trip. I'll compare the results and investigate any significant differences. This process has successfully detected several failed mechanical tire pressure gauges.

Tom said:

Depends on the TPMS. With PPro, if the sensor doesn't check in periodically, the main (dash) unit alarms. There's no question that it alerts you to a lost signal from the sensor, irrespective of the cause (low battery or just lost signal).

No disagreement about relying solely on a TPMS, but it's a lot easier than trying to continually take the tire pressures as I'm driving down the highway.

FWIW I check the tire pressures with a regular gauge before screwing the sensors on at the beginning of every trip, and again periodically during a trip. I'll compare the results and investigate any significant differences. This process has successfully detected several failed mechanical tire pressure gauges.

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I agree with this 100%.  Also, don't forget that when technicians mount and balance these tires, I can be pretty sure that aren't the most gentle with these types of things, and the chance for error increases dramatically.  They are definitely prone to being damaged during tire mounting and dismounting procedures at the tire fitters. Banded sensors are attached to internal rim dropwell circumferences and are prone to damaging the tire's bead during tire fitting operations.

I haven't observed any issues with tire changers that would cause a problem with the PPro sensors; I'd merely remove the sensors before entering the shop, and replace them afterwards.

OTOH when I had tires changed on our Suburban, the tire jockeys at WalMart wouldn't/couldn't change the valve stems because of the OEM sensors. Made no sense to me, since WM sold replacement stems with sensors.

jjkz24 said:

Next question (just for fun ), how many of you VISUALLY check your fuel tank before a trip, or...rely on the fuel gauge?  8)

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I rely on the odometer and the mpg, DTE information as well as the fuel gage and the fill gage on the pump when I buy fuel.  You make a great point though... there's a post on here somewhere that lists the most likely kinds of wrecks and IIRC the tires aren't involved in the top 10... it's mirrors, antennas, roof a/c units and gas station canopies that are the most frequent wrecks.  Cockpit errors.

There's ton's of stuff that doesn't get checked... just turns out that TPMS is a system that's easy to build, easy to install after market and easy to sell.  No one I know checks (or has a monitor) the fan belt, or the radiator hoses, or the steering linkage, or the frame structural integrity, or the wheel bearings, or the engine bearings, or the fuel lines, or the brake pedal, or the gas pedal, or the transmission linkage, or the headlight switch wiring, or a gillion other things... many of which can be as dangerous as a leak in a tire.  The pilot probably recalls the aircraft in Hawaii that practically fell apart in flight because of structural corrosion.  How many fires have resulted from a leaky fuel line spraying diesel fuel on a hot engine?  Now there's a market for someone... an engine camera that allows us to watch the engine in addition to: monitor the pressure on 10 tires, watch the toad, the coolant temperature, the oil pressure, the brakes, the fuel gage, the outside temperature, the transmission temperature, the mpg (instant, average, and leg), the odometer, the speedometer and all the mirrors as well as the road ahead.  How can any human manage all this and have fun at the same time??????????  I tell you, it's impossible, LOL.

the tire jockeys at WalMart wouldn't/couldn't change the valve stems because of the OEM sensors.

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When we replaced the tires on the truck last year Discount Tire included new metal stems with sensors as part of the package.

Thud test will tell you that the tire is flat, not low on air pressure, 10 or 15 lbs will not sound much different