Broken tire stem

Rexer66

Member
:
2008 Mazda cx9 grand touring
Hello,

I have 2 broken stems on my car yes I was stupid and did not know putting metal caps on could screw them up so all 4 are damaged but 2 are broken off at the threads. Does anyone know of a cheaper fix because we are going on vacation and I would rather save the money until after but if I have to will pay because we are driving from New York to Florida so I want to be safe. Any thoughts?
Thanks,
Kenny
 
You should be able to jurist have discount tire replace the stems unless you have tpms.

I don't see how metal caps could cause this unless they were over tightened though.
 
I don't see how metal caps could cause this unless they were over tightened though.


I suppose the metal threads from the cap and the metal threads from the stems could have "rusted" together, making the cap impossible to remove.

Probably would be a good idea to put a bit of grease on the threads if you use metal caps to prevent this.
 
Hello,

I have 2 broken stems on my car yes I was stupid and did not know putting metal caps on could screw them up so all 4 are damaged but 2 are broken off at the threads. Does anyone know of a cheaper fix because we are going on vacation and I would rather save the money until after but if I have to will pay because we are driving from New York to Florida so I want to be safe. Any thoughts?
Thanks,
Kenny

I'm assuming the metal caps you used damaged the threads in either of three ways:

1) most likely, metal cap had too much mass when spinning at highway speeds and stressed the stems until they broke

2) unlikely, but maybe incorrect mismatched threading? but that would have meant you really forced on those metal caps, which I don't think you did.

3) this is unlikely but maybe dissimilar metals between valve thread and metal cap caused damage due to different coefficients of thermal expansion, ie in hot weather, the metal stem expands but the metal cap prevented it from expanding and the threads broke off.

This is why most shops use the lightweight flexible gray color plastic valve caps for tpms stems, the metal novelty caps like skull heads, eight balls are very bad for tpms metal stems.

I think this will work for you, give this a shot, basically you mill out the existing stem and hand tap new internal threads then screw in a new valve stem, this is a low cost alternative to buying whole new sensors
https://m.youtube.com/watch?v=jCsFB0mDj-U&feature=youtu.be

I think if only the thread portion of the stem is damaged, I think you'll be ok, just no valve cap. If the valve stem is bent, I would highly recommend getting it fixed before driving from NY to Florida.
 
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Ouch, that is not Good. I have never had issues with the caps but this is also the first vehicle I've owned with tpms.
Depending on how much you want the tpms to work and how annoying the alert is (I haven't seen it on mine yet) you may just have regular stems put in - if that's even possible.
 
That looks like a great system have you used it or has anyone else on here? How did it work for you?
I'm assuming the metal caps you used damaged the threads in either of three ways:

1) most likely, metal cap had too much mass when spinning at highway speeds and stressed the stems until they broke

2) unlikely, but maybe incorrect mismatched threading? but that would have meant you really forced on those metal caps, which I don't think you did.

3) this is unlikely but maybe dissimilar metals between valve thread and metal cap caused damage due to different coefficients of thermal expansion, ie in hot weather, the metal stem expands but the metal cap prevented it from expanding and the threads broke off.

This is why most shops use the lightweight flexible gray color plastic valve caps for tpms stems, the metal novelty caps like skull heads, eight balls are very bad for tpms metal stems.

I think this will work for you, give this a shot, basically you mill out the existing stem and hand tap new internal threads then screw in a new valve stem, this is a low cost alternative to buying while new sensors
https://m.youtube.com/watch?v=jCsFB0mDj-U&feature=youtu.be

I think if only the thread portion of the stem is damaged, I think you'll be ok, just no valve cap. If the valve stem is bent, I would highly recommend getting it fixed before driving from NY to Florida.
 
sorry, I've never used it before, I just happen to come across it after googling tpms stem repair, was just letting you know your options.
 
That replacement kit is amazing found one on eBay for $120 shipped everywhere else is $165ish did all 4 takes about 10 minutes a tire and 15 for the lock tight to set up well worth it and the kit was less than the shop wanted to charge me for 1
 
That replacement kit is amazing found one on eBay for $120 shipped everywhere else is $165ish did all 4 takes about 10 minutes a tire and 15 for the lock tight to set up well worth it and the kit was less than the shop wanted to charge me for 1

That's AWESOME Rexer66 !! glad you were able to fix it without burning a hole thru your wallet !!

very good info to know for anyone with broken TPMS valve stems. And remember: NO MORE METAL VALVE CAPS :)

Actually, what was the main reason the stems broke ? was it too much mass from the metal valves that caused the stems to break ?
 
On 2 of the stems the caps ended up corroding causing the threads to erode away making it possible to inflate tires but not without air blowing all over. The other 2 the caps ended up getting stuck on my assumption was they corroded together I needed plyers to get them off and they literally came off, broke right off exposing the pin making it impossible to blow up. The new stems come with metal caps but my assumption is they are made to go together and it seems they cover the majority of the stem which gives it less area exposed to the elements. It's been a couple days and tires still have air with no slow leaks I'm very pleased with the product did all 4 for about the price of one.
 
You should be able to jurist have discount tire replace the stems unless you have tpms.

I don't see how metal caps could cause this unless they were over tightened though.

Cheap metal valve caps can become fused (ok--not really fused, but I'm not a scientist) to the stems.
 
Cheap metal valve caps can become fused (ok--not really fused, but I'm not a scientist) to the stems.

I'm not a scientist, either. But I am an engineer. And they do become fused. It's the same phenomenon that glues a battery cable to the terminal after a while.
 

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