Good work. Wouldn't be cheaper to just drop in a good replacement engine? Disclaimer, I haven't looked at prices of an N55.

I just retimed my N52. Can't imagine it being much different for the N55. Check Nathan's BMW Workshop YT channel. He might have something for you on there regarding the procedure. TIS should tell you as well.

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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)

2006 X5 4.8is Build 11/05 Maintenance/Build Log
Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

2010 X5 35d Build 02/10
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