[nazali]

So, a word to the wise, and partly my fault.

I always check tires monthly, since getting TPMS I have been checking it using the system, not an airhose
as a result I didnt remove the caps for MANY MONTHS.
Now I bought official BMW tirecaps (metal) and the salt corroded them to the tire sensors, meaing my tire guy needed to use a pair of channel locks to remove them,
This was weird because last season on my 1 series I had no problems
Then remember that the TPMS sensor is not BRASS as an ordinary vavle cap would be but some kinda alloy. and the BMW metal cap covers have BRASS inserts.
Physics 101 on 2 dissimilar metals, salt, ice snow.... CORROSION,
NOW, had I removed them monthly I would have had no problem, but I think since beginning of season to now they were not touched.
His worry was it could have snapped the TPMS sensor.
Luckily all I got for my trouble is 4 gnarlly and torn apart valve caps but the sensors where all good.
he slapped some A/sieze on them so it should happen again
I'll see if I can get some pictures
!

[dradernh]

Originally Posted by nazali

Now I bought official BMW tirecaps (metal) and the salt corroded them to the tire sensors, meaing my tire guy needed to use a pair of channel locks to remove them

Were either of these the valve caps you bought: https://www.realoem.com/bmw/enUS/sho...diagId=36_2402?

[nazali]

WOW interesting,
NOW, I know they have the BMW M on them and I got them from my dealer, I just picked them up from a shelf, didnt bother to ask
but these are they

Originally Posted by dradernh

Were either of these the valve caps you bought: https://www.realoem.com/bmw/enUS/sho...diagId=36_2402?

[nazali]

I don't have the receipt anymore (from my old 1 series) so they "could" be different ?
but they def don't look like the picture right ?

[nazali]

when he pulled them off, what looked like "salt" ? a fine white powder basically poured out

[dradernh]

Originally Posted by nazali

I don't have the receipt anymore (from my old 1 series) so they "could" be different ?
but they def don't look like the picture right ?

No, they don't look like the unit in the picture, do they.

I do wish some aspects of our cars weren't so involved. Oh well, at least they have M stripes everywhere you look; that's not such a bad tradeoff, right?

[nazali]

yeah there is that, next time I speak to my parts guy's guy I'll have a word with him, but it kinda makes sense that there is a specific part, BMW, high end luxury sports car as such I guess you can't just put any parts on it LOL even OEM it seems

[John in VA]

BMW caps came with a warning that the dissimilar metals could corrode - this was a decade or so ago.

[nazali]

txs to be honest, these came from my old 1 series as said, so was working fine (brass on brass) I didn't see any warning, could have been on the instructions. and I guess as I said physics 101 right.

I'm sure other people hae this, I just picked them up from parts they were on display, I may or may not have asked, I may not have thought it was worth asking.

I'm guessing any parts which could have a problem should probably not be on display as if they are just bog standard works on anything kinda part.

As I said something that looks pretty for your car maybe should have a health warning LOL

as I said just a warning, now I know, also I should have been manually checking my air psi.

Originally Posted by John in VA

BMW caps came with a warning that the dissimilar metals could corrode - this was a decade or so ago.

[aerobod]

Originally Posted by nazali

txs to be honest, these came from my old 1 series as said, so was working fine (brass on brass) I didn't see any warning, could have been on the instructions. and I guess as I said physics 101 right.

I'm sure other people hae this, I just picked them up from parts they were on display, I may or may not have asked, I may not have thought it was worth asking.

I'm guessing any parts which could have a problem should probably not be on display as if they are just bog standard works on anything kinda part.

As I said something that looks pretty for your car maybe should have a health warning LOL

as I said just a warning, now I know, also I should have been manually checking my air psi.

In Canada the 1-series didn't come with TPMS, only FTM using the ABS, so conventional metal valve caps were fine. Now they have added TPMS to recent Canadian cars, the dissimilar metal in the TPMS valve stems and attachment nut causes the electolytic corrosion.

[nazali]

yes, correct, what I meant was, my 1 series, had the FTM and I changed out the plastic ones for the m ones, when I went to the 2 series I had my only caps from the one series (the m ones) if that makes sense

Originally Posted by aerobod

In Canada the 1-series didn't come with TPMS, only FTM using the ABS, so conventional metal valve caps were fine. Now they have added TPMS to recent Canadian cars, the dissimilar metal in the TPMS valve stems and attachment nut causes the electolytic corrosion.