Caution-Frozen Valve Stem Caps
Thread Starter
Super Member
Joined: Oct 2007
Posts: 917
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From: Manassas, VA
10 Cayenne GTS, 07 Porsche 911 Turbo
Caution-Frozen Valve Stem Caps
Yesterday I wanted to check the tire pressure on my wife's BMW X3 that came wirth a tire pressure monitoring system (TPMS). When I tried to unscrew the first metal BMW valve stem cap it was frozen and the rest were the same. I couldn't even get it off with a pliar and may have stripped the head. So I called the dealer this morning and they said you should not put metal valve stem caps on a car with TPMS because they will freeze/rust in place. Trust me, it's TRUE! You should only use plastic or rubber valve stem caps. I also have AMG metal caps on my SL (my BS does not have TPMS) which explains why they are so difficult to unscrew. Just a heads up to avoid a future and potentially expensive problem.
Last edited by LOVEMYBS; Mar 29, 2010 at 12:27 PM. Reason: edit
Thread Starter
Super Member
Joined: Oct 2007
Posts: 917
Likes: 1
From: Manassas, VA
10 Cayenne GTS, 07 Porsche 911 Turbo
Steel valve stems vs. copper and rubber for non-TPMS cars. I'm told aluminum and steel under the right environmental conditions (e.g. we just finished with a lot of snow, ice and rain in VA) will bond and forge a very tight seal.
