Topic: Re: Unity tire pressure / valve stems (Read 4537 times) previous topic - next topic - Topic derived from Unity MB bedding

We have a LTV Unity IB with Iker tire pressure monitors which have proved useful especially since mfg published Utube programming instructions. Recently an inside rear tire started loosing air assumed to be a puncture. It turned out to be a valve stem extension which LesShwab tire service removed stating the failure was #1 cause of dual tire flats, saying  we always remove them. This action makes access to sensor nearly impossible as well as inflation.
Are valve stem extenders really an inherent problem?
I’m running near 80psi and after extensive study will drop to 70, I believe our rig is close to 12000lbs. No notable center wear.
Any insight most welcome.
Thanks

What kind of wheel do you have steel or Alcoa?  The Sprinter forum; Unity sub forum has all kinds of posts about what you need to do about the valves when you have a TPMS

For the inner dually you need one piece long valve stems by Borg, they  will solve all of your problems.
To determine how much air pressure to use in each tire, you need to get the actual travel weight at each corner, then consult the tire manufacturers load tables.  I think you will find that 80 psi is way too much.  And rears use less then fronts.
https://www.michelinb2b.com/wps/b2bcontent/PDF/RV_Tires_Brochure.pdf#page=20

I'll pursuit actual weight and go from there  ... surly valve stem extensions aren't that so problematic that they can't be used ?

We have 2021 Unity van on Mercedes Chassis. We had a tire stem break on an inner tire and the inner tire was at "0" but there was no notification or light warning. It could have been a very bad outcome. Thank goodness my husband had just decided we should check the pressures before heading off across the desert!  We were able to get a mobile big truck service to replace the valve with one he just happened to have, which was lucky. We now carry spares. We installed to separate tire pressure monitor that screws onto the stems and sends a signal to a device on the dash with a remote sensor that sits on our front dash. Having that ongoing feedback is worth it!

You're lucky and like so many other people they don't put the right stems on to begin with and hope they'll get lucky. The stems that you should be using are about a $100 . It's really sad to see the people that try not to buy the proper stems to begin with just to save a $100 it costs some 500 to a 1000 later. You need to put the right stems on and I believe they're called Borg stems or something like that. Maybe someone will be able to give you a link. No need for extra stems of you get the right one to begin with.

Regular steel wheels come with rubber stem valves.  If NON rigid extenders are installed, the rubber vibrates and cracks/leaks. 
Borg valve stem extenders allow access to inner tires, are all steel, and allow TPMS installation.  Not expensive.  Order online from
Your Tire Shop Supply | Supplies for Tire Shops 
Their called “duelly valve kit for sprinter”.  One type for steel wheels, other if aluminum.  They have a sizing chart for tires.  Any TRUCK tire shop can install.  Mine work just great.  Good luck!

I had been planning to upgrade my inner stems and was all set to buy the stems from them until I saw their outrageous shipping charges. So I searched and found the same thing with free USPS shipping here Dually Valve Stems for Mercedes Sprinter Archives - Always Shiny Wheels and RV

We have a 2019 Unity IB with  LP Onan Generator.
There’s all good fuses at chassis fuse block under floorboard but zero voltage at start solenoid lug connector that appears to be sweaged on cable. ( I haven’t probed beneath adjacent insulation ) I see no apparent damage underneath coach ?
Coincidentally I had to repair propane tube going to carburetor because rhodent chewed all the way thru it. Just after that repair  it turned over a few time and the I couldn’t find  any voltage at solenoid. Crazy! It turns over with jump start.
Odd that 1/0 cable would fail between chassis & gen. ?