What does the Liquid Moly additive do? Sounds promising. I occasionally get rattle on my 4.6 with 10k on it. No discernible pattern to it either. It just sat for over a week and no rattle when I started it, occasionally it will rattle. Even after just sitting overnight. My oil filter housing is only a couple years old and would be thought to replace so I hope it’s ok. It’s the Gulf version which allows me to plumb in the oil cooler, and was hard to track down 2 years ago.

I’m thinking of going to a 10w-30 perhaps and see if that will stay in the vanos longer. I will say the 4.4 I took out of the x5 rattled for close to 20 years if I recall, so I’m not overly concerned. Someday I’ll pull that motor apart and see how it looks inside. Hopefully as part of a rebuild. I’m thinking of putting it in an E34 5 series these days. I love the E24 6 series, but they are too pricey for a straight, (mostly) rust free car these days. The E34 has the same shark nose look, which I like.

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Current
Original owner 2002 E53 X5 4.4i to 4.6i swap
2025 G06 X5 50e
Former
1972 Audi Fox
1986 Saab 900S
1996 BMW Z3
1998 BMW E36 M3 Sedan
2004 BMW E46 M3
2006 Audi A3 Quatro
1993 Mopar 318 Jeep Grand Cherokee
2015 V6 Jeep Grand Cherokee