Have you located any B46s for sale? A better solution may be to rebuild your motor. If not, and you don't feel like downgrading to the B44, then please put an S62 in it. "Should" bolt right up. There is also an LS1 swap, there a hundreds of LS1 BMWs now... Just no X5s to my knowledge.

Another kind of silly idea would be to try and find a wrecked 4.6is with an intact motor. Or, just buy another cheap 4.6is for $10k and take the motor... Sell the rest of the parts to guys like us.

I just really question the likelihood of finding a used 4.6 motor. There may be new B46 crate motors in a BMW warehouse somewhere, that would be a real treat to have.

Hopefully you can use this as an opportunity to rebuild the truck stronger than before. Still a hard pill to swallow.

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2002 X5 4.6is - Titanium Silver / Black Alcantara - Dinan Stage 2 - Bilstein/Eibach - Brembo BBK ----SOLD---
1993 318i - Brilliantrot / Tan - bone stock daily driver