Community Forums

Bob_C · 08-23-2019, 07:36 PM

Back in the fifties and sixties, folks used to have oversized dice for valve caps.....on rubber valve stems.....the non flow thru type are lighter if you remove the anti theft shell....

NXR · 08-23-2019, 09:07 PM

Quote:

Originally Posted by bob caldwell

Back in the fifties and sixties, folks used to have oversized dice for valve caps.....on rubber valve stems.....

True but everything on those cars was solidly built. Today companies shave things to the minimum they can to cut costs and boost profits.

Think about what happened when certain absorption refrigerator manufacturers decided to reduce the wall thickness of the tubing. They worked for a while and then it was fire after fire as they aged.

We read a lot about blowouts, particularly front tire blowouts, causing massive and sometimes fatal accidents yet we willingly accept the risk of a piece of thin flexing rubber, something that is very close to road debris and rocks, failing and causing a rapid loss of air. Everything works well until it doesn't.

Given the choice of no TPMS versus a TPMS on flexible valve stems I'd go with the TPMS every time. The associated risks of an underinflated tire or an undetected flat tire on a dual pair is higher than a valve stem failure to me.

But I'd still do what I can to reduce the valve stem risk somehow. Brace the valve stem somehow, whatever.

Kudos to the original poster for proactively taking steps to improve their safety and that of the people around them.

Ray

Spk64 · 08-23-2019, 09:11 PM

When I setup the Jeep the valve stems were rubber with the chrome sleeves. One trip with the TPMS sensors and I was convinced those had to go. Had marks on every wheel where the TPMS sensors were constantly flexing and banging against the wheels. Had short metal stems installed, no worries now.

Dennis_K · 08-24-2019, 03:47 PM

When I first put them on my car trailer it had rubber stems. After my first trip, when I got back I noticed the paint on the rims was gone where the sensors had been hitting. I replaced with metal stems before the next trip.

NXR · 08-24-2019, 05:20 PM

So today I decided to add 5 psi to each tire since the temps here are dropping. Below are some pictures of the TPMS sensor on the inner duals with a metal valve extension.

Interestingly, the driver's side one seems to be accumulating dirt around the TPMS sensor on the rim but nowhere else.

The passenger side TPMS sensor has developed a flat spot from hitting the rim. Both sensors are very close to the rim because of how the solid metal extension is positioned, maybe 1/4" or less to the rim.

The TPMS sensors have been in place for only 400 miles. These are the new TST 507 sensors, the ones that no longer have the spinning anti-theft cap and that also have a user-replaceable battery. They weigh 0.6 ounces each.

I'm thinking of adding a small glob of RTV to the gap between the valve stem extension and where it comes through the outside tire. That should give it some more stability.

Ray

Spk64 · 08-24-2019, 05:36 PM

I think you need the rubber stabilizers that keep the stem centered in the hole.
When I added them to my inner dualies the kit came with them.
https://www.shinyrv.com/product-cate...y-valve-stems/

NXR · 08-24-2019, 08:22 PM

Quote:

Originally Posted by Spk64

I think you need the rubber stabilizers that keep the stem centered in the hole.
When I added them to my inner dualies the kit came with them.
https://www.shinyrv.com/product-cate...y-valve-stems/

I looked for them but got lost trying to figure out what I needed. I mean, what the heck is a "hand hole" in a tire wheel? They are Alcoa 22.5" wheels on a 2019 F53 chassis.

Ray

rmueller · 08-31-2019, 07:50 AM

I've had my TST sensors on rubber valve stems on my Jeep and MH for some time now, no issues...but I might look at some prevention.

After reading this, I think I'm going to cut a few pieces black rubber hose that I can support the sensor and stem to keep it from vibrating or rubbing on anything.

I did make a more fatal mistake with the sensors, I screwed them on super tight...don't do it!!!! It bent the pin in the valve stem insert so it no longer sealed when I took the sensor off. Had to have the valve stem inserts replaced, luckily the service manager at Silver Lake Auto and Tire in Oconomowoc did the job - no charge...awesome customer service.

rm

JCM · 09-01-2019, 11:30 AM

When I had rubber stems, I had 2 fail at -30f. These were on my toad. Since going to metal stems - no problems.
The rubber stems were cracked where they "rubbed" against the rims.. GO METAL BEFORE YOU NEEDF TO!!!!

Dark Sky · 09-02-2019, 08:34 PM

I run metal stems on all my vehicles whether using tpms sensors or not. Several years back I was riding with a group of motorcycles. We stopped for lunch after a high speed run (west of the Pecos in Texas) and after lunch found one of the BMW's had a flat tire. His rubber valve stem had cracked and failed. It could have been fatal if it had let go earlier. Metal stems are cheap insurance.