Good day!!!

I actually think that extension piece is the input shaft of the Transfer Case... I'll have to look at my spare TC tomorrow... The spare 2006 automatic I have in the garage looks like your first picture... And, I think the part in the third picture did not originally come with the X5 from the factory... It would be a nice option to have... Is that the police edition?!

It is great you got it and didn't have to pull the trans again...

Thanks for updating so others will have a reference!!

Cheers!!!

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2001 E53 X5 4.4i (03-07-2001 build date) White exterior / hellbeige interior (6MT swap vehicle - Manny)
2002 E53 X5 4.6is (12-20-2001 build date) Imola Red exterior / M-texture interior (Red)
2003 E53 X5 4.4i (06-26-2003 build date) Silver exterior / Black interior (Silvester II)
2008 Mini Cooper S ragtop (04-17-2008 build date) Dark Silver exterior / Gray interior ( Topless)
BMWCCA member (#4745)