By Roger Marble
Sometimes my wife accuses me of being too negative because I seem to always come up with something negative about almost any topic. I really don’t consider it negative when I see there might be a way to make something or a situation better.
I guess it’s in my DNA to never be satisfied and always want things to be better, easier, safer or more durable. The simple act of checking tire air pressure is an example.
Pushing on valve stems can damage them
Each time you use a hand gauge to check air (morning of every travel day) you are pushing on the valve stem. If you have a standard short (less than 2″) valve stem, no problem. BUT for dual tire positions as seen on almost all Class A and Class C motorhomes there are either valve stems that have a bend in them or there are extenders of some type. Pushing on a bent or angled stem will place a torque on the stem mount in the wheel. This can lead to eventual degradation of the rubber seal between the wheel and the stem.
Here is what happened a few years ago to the tire of a friend of mine. He was not running a TPMS so got no warning that the valve stem developed a leak at the rubber gasket between the wheel and the stem.
The tire lost air and the steel body cords fatigued due to over-flexing of the sidewall, which resulted in the sidewall “blowing out.” Initially he thought it might be a “defective tire,” but when inflating the new tire it was discovered that the valve stem no longer had a solid rubber gasket at the wheel. So obviously this was not a “defective tire” – as any tire can fail if you do not keep the air in it. Soon after this he installed a TPMS.
If you have some type of extenders, flexible hose or hard line, you might end up moving or bending or even loosening the extender if it isn’t supported when you push a gauge or air chuck on the outer end.
An advantage to using a TPMS you may not have thought about
One advantage of running a TPMS that few people consider is that the TPMS gives you a pressure check each morning, as well as a continuous check while you drive down the road – so this eliminates the need to push on the stem or extender.
TPMS eliminates this torque force on the valve stem mount along with saving you the time needed to go out, get down on your knees, remove the metal valve cap, push on the stem and get a reading. Lots of fun if it is cold or raining. (Not.)
I prefer to just turn on my TPMS in the morning and, after my cup of coffee, look at the monitor on the TPMS and in a minute or two know the state of inflation for every tire.
No muss or fuss – plus the additional benefit of no torquing the valve stem mount.
Here’s more information on valve stems: Valve stems, cores and caps, “Oh my!” – And how tight is “tight enough”?