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Topic: TST TPMS error! (Read 634 times) previous topic - next topic

TST TPMS error!

Not being familiar with dual tires, I made a simple error in judgement on installing a system I have used for years on the Ram.  Because of clearance issues for the inside tire, I slightly pryed the valve stem out to install sender.  It then rested on the rim which I did not like but tried it for a short 55 mile run.  We parked for the next two nights and the first morning check showed 66 pounds which was down 17 cold.  Inflated back to 83 and removed sender.  Checked next morning no loss...the angle must have caused the Schrader to discharge slowly.  The driver side quit transmitting so I checked it and when I removed the sender found that valve would not stop discharging.  Not having the right tool and having no idea what to expect I stopped at a nearby truck tire shop and they replaced valve and the associated extention for 10 bucks.  20 with tip as the guy took his time and explained how they came together.

I have ordered the 180 and 45 TST sell for their senders.  One more lesson learned.
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: TST TPMS error!

Reply #1 –
Any TPMS sender mounted on the stem can cause leaks at the valve stem grommet. If you disturb the position of the stem, you are likely to cause a leak. If you pry on the stem, you are likely to move the stem in the grommet. Also, the weight of the sensor will exert force and may flex the stem in the grommet while underway. Problems are more likely if the grommets are old and no longer supple.

I added TST TPMS to our first coach. It was a twelve year old SOB DP. Tires and grommets were old. I, the proud new owner, was new and in serious need of education regarding a big vehicle. We had one tire that lost pressure only while the coach was moving. We had another tire go completely flat while parked for a very short time. Both problems were fixed by installing new valve stem grommets.

I added Pressure Pro TPMS to our Foretravel and towed vehicle about three years ago. I've experienced no leaks and the system has performed well. I plan to have new grommets installed when we get new tires this year. I'll check with Herman Power Tire Company regarding whether to replace stems. I did have new metal stems installed on the towed vehicle before I installed TPMS on it.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: TST TPMS error!

Reply #2 –
Metal stems were a must on the first rig.  I was holding off on the towed till I can get them.

J D is there any problem using the 180 and 45 extensions?
George and Steph
1997 U270 36 Build 5081 "Honu"
1180w Solar 400A lithium all Victron house system
Motorcade 17670, SKP 128300, FMCA F459019
73 VW Camper, 79 VW Camper, 2363 Sunline, and an Arctic Fox 25P

Re: TST TPMS error!

Reply #3 –
Quote from: George and Steph –
J D is there any problem using the 180 and 45 extensions?
I can't provide a reliable answer to that question. I can say that I would not use them.

On two coaches, I've had the short, straight little extenders that extend the stem from the inner dual to an easily accessible point outside the outer wheel. They use the rubber stabilizers in the hole of the outer wheel to help stabilize the extended stem. The only problem I've ever had with those was a valve core that developed a leak. The leak appeared to be a failure of a part rather than a flaw in design.

I expect to buy new tires within the next two months. I expect have them installed at Herman Power Tire Company in NAC. I plan to seek their recommendations regarding the appropriate valve stems to install for safety, reliability, and convenience while using the Pressure Pro sensors.

My current installation uses the short, curved stems that terminate in one of the holes in the Alcoa wheels. The inside duals use the "shorty" straight extenders with rubber stabilizers in the outer wheels. It's not a difficult task to add or remove air from a tire. It does take a bit of contortion to remove/install the sensors on the outside duals. I can always check pressures at the control panel. I find that I only need to adjust pressures a couple of times a year. Those adjustments are related to ambient temperature changes.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: TST TPMS error!

Reply #4 –
Have a question related to this....

For my outside dual, the valve stem turns sharply back toward the inside dual into a wheel hole and  i take the pressure by putting the gauge into the hole and pulling backward onto the stem to take pressure, or to add air.  (Hope that makes sense!)

I expressed to John and Steve at Fredericksburg my wish for easier access to the outer tire stem.  Steve showed me that rather than turn that valve stem back into the hole toward the inside dual, he had the valve stem point toward the hub, good access.  Maybe that the 45.

Then John showed me a 180 and that too looked better than what i have, easier to use.

John and Steve  had the same TPMS and said these stem arrangements worked well.

Which leads me to this....why is that outer tire stem routed back toward the inner dual tire on my set up?  Why not just turn it outward or at least as Steve's, toward the hub?
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: TST TPMS error!

Reply #5 –
Mike, I think the outside tire in the rear should have the valve stem pointing out.  I wonder if that wheel might have been in the front at one time. 

Make sure you check the valves in the valve stems are snugged up.  We had a low tire once and it was the valve.  Our TST TPMS alerted us to that fact before we drove off.  I have had my TST with the flow through sensors for four years. I had one sensor that had a very slow leak. it would lose 2-3 lbs a week.  With it not on that tire held air all winter long.  I always have a couple of spare sensors, spare O-rings, battery covers and screws.  I check my tires with a tire gauge every day before we drive.  I depend on the TPMS to let me know if something is changing.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: TST TPMS error!

Reply #6 –
Mike,

<DISCLAIMER> I am not an expert regarding the stem placement. </DISCLAIMER>

The placement of the stem pointing inward is an orientation that can be used on any position on the coach. It is also a protected position for the stem. That is the way my coach is set up. A standard heavy duty air fill head will easily fit any of the stems for inflation, measurement, or adjustment.

PP sensors go on easily on the front tires. They go on easily for inside duals with one of the "shorty" straight extensions (with supporting rubber insert in the wheel). They go on the outside duals with moderate effort.

When I have new tires installed, I plan to ask about "special" orientations for stems. A change in the outside duals could enable easier access.

J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: TST TPMS error!

Reply #7 –
Quote from: Roger & Susan in Home2 –
Mike, I think the outside tire in the rear should have the valve stem pointing out.  I wonder if that wheel might have been in the front at one time. 



Maybe different on motorhomes even though I don't know why, but the tire shops always put the outside stem pointing in on the dually's on my trucks.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: TST TPMS error!

Reply #8 –
I suspect that is because that outside tire might end up in front or on the inside.  The fancy rims on the MH make that less likely.  Point them where it is easy to do what needs to be done. 
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: TST TPMS error!

Reply #9 –
Thanks Craneman and Roger...thought msybe a safety thing but seemed unreasonable for that...and you point out why may be as is.  So, from your help, Going to change to point out....do they have to take the tire off to do this?
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: TST TPMS error!

Reply #10 –
I need a TPMS system! What Model Pressure Pro is the better one that does not leek and works well?
Art
1997 Prevost 40'
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Re: TST TPMS error!

Reply #11 –
I have the outside dually stems pointed out for almost 7500 miles now with no issues since I put on the new shoes.  What a joy!  It is so much easier to remove my Tire Traker sensors to adjust air pressures or just verify the sensor readings match my stick gauge.

BTW, for those of you with the original Tire Traker system, TireTraker TPMS - LIFETIME WARRANTY you can trade in your old monitor for a new one and receive a $50 discount.  Not trying to sell anything, but the new monitor works with the old sensors and provides pressure/tire updates without having to move the coach - that was my biggest issue with the old system!
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Mark & Mary Benko
Former coach: 2005 U295 3823
Jeep Cherokee, Honda Fit

Re: TST TPMS error!

Reply #12 –
I have had my outside dual pointed out for over ten years. No problems over hundreds of thousand miles.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon
 

Re: TST TPMS error!

Reply #13 –
Mike, best practice is probably to take the wheel and tire off, break one bead, remove the valve stem and put a new gasket/seal on and reposition and reinstall, remount and reinflate the tire and put it back on the coach.  On my valve stems the rubber seals are in the inside and the nut is on the outside.  I had new valve stems installed, $50 per tire, mostly labor.  And make sure they use appropriate tools for setting the lug nut torque.  Good shops will have a hydraulic torque wrench.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN