My X wasn't leaking oil as bad as yours, but it did leaked oil. I ended up replacing (DIY):

Both valve covers
Both upper timing chain (might explain why yours is leaking at the front)
Both VANOS seal

One thing for sure, if you have oil protruding into the spark plug areas...it's time to replace the valve cover gaskets...upper timing chain gaskets, too, while you're there.

I did both at about 94K. The rubber gaskets were hard as rock--explains why they were no longer effective.

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2003 X5 4.4i Titanium Silver