Chrome valve stem caps with TPMS?

**iaonbb** · 09-14-2009 01:00 PM

Anyone ever heard of a problem using chromies with TPMS sensors? I was warned a couple years back on a Yota board about using them on my '07
4Runner. Owners stated they would essentially become stuck on aka "welded' to the valve stem due to heat or something like that (sorry can't remember exactly why).

Found this on a Bimmer board: "
yes, chrome plated brass caps (this is what normal metal caps are made of, even bmw ones) will fuse to the aluminum valve stems that the tpms system uses. you may end up having to cut off the stems to get the caps off. galvanic corrosion between the brass and aluminum."

Wondering if anyone has experienced this? I think I'm going to stick with the plastic or search for some chrome plated plastic ones to be safe. Thought this was a worthwhile topic if nothing else for others who might otherwise be unaware...

**schmally** · 09-14-2009 01:02 PM

you can also keep them lubed.. and sealed

**{PMS}fishy** · 09-14-2009 01:09 PM

A dab will do ya.

**SkiWalk3r** · 09-14-2009 01:24 PM

I have the chrome stems on my car and have not had any issues like this. I just had them all topped off before a road trip and they came off with ease.

**userbbc** · 09-14-2009 06:56 PM

Had them on my old TL where they repeatedly seized on to the valve stems. The times where I took it in to Acura for bent rims, they forced them off, ruined the sensors, but replaced them under warranty, never bothering to tell me to stop using metal valve caps.

The last time at Firestone getting a new set of tires, they forced off the valve caps and I ended up having to replace three out of four sensors out of pocket. Firestone did actually bring up the fact that metal to metal contact would generally seize up, especially in east coast rain, snow, and road salt. Chrome caps on non-TPMS rubber stems should be fine. As well, lubing and sealing should alleviate the metal cap to metal stem situation but still a matter of ROI.

**iaonbb** · 09-15-2009 11:19 AM

I'm sticking with plastic then. Don't want to take a chance on somethign so litle causing so much damage.

**userbbc** · 10-07-2009 08:24 AM

came across this article and thought of this thread.
Depending on the type of aluminum they use on the valve stems, chrome/brass could be a very bad mix with aluminum.

http://www.engineersedge.com/galvanic_capatability.htm