If they are like the e46... they are hydraulic mounts. I have seen the e46's fail in the early 100's miles as well. Plus the N62 weighs a decent amount more and has a lot more torque than an M54. So even though the mounts are bigger, I'm sure they see more stress than those on the e46.

I need to do mine as well... 114k miles. But I've been able to feel vibration from them under 100k miles. I think these trucks are just hard on mounts.

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2005 X5 4.4i Build 04/05 Maintenance/Build Log
Nav, Pano, Sport (Purchased 06/14 w/ 109,000 miles) (Sold 8/15 w/121,000 miles)

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Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

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