I was able to do a mod similar to this with my Mercedes a few years back. They updated the keys from black to chrome/black and they just looked totally different from before. The internals were different as well. Super nice. I simply ordered a new key with my VIN and Mercedes made it for me in the new key form. Given the 3 different radio's needed to make it work inside the key plus the complicated mercedes ignition I'd think BMW could pull it off. Worked great. I wish BMW did this.

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~2003 X5 4.4i~