I tried to do this with my 2002 X5 3.0i after I bought it with no nav. It turned out to be about a $4000 proposition when it was all said and done. Would be much cheaper to just by an X5 with it already.

With that said, the '06 and older X5's used iBus which was much easier to do. Everything in the new X5's is Fiber optics. Not to be a nay sayer, but even if you get all the right components, the new X5's require require coding from the dealer when you install any electronic component. For example, to install Sirius (which was plug and play in the old E53) is 2 hours of labor for coding.

Everything is software driven as all modules on the BMW MOST bus have to be running the same software version and be coded to accept one another.

If you have the option, just buy the X5 with nav. You'll save yourself money, time, and frustration.

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Previous: 2002 X5 3.0 / 121,000 miles
Current: 2007 X5 3.0si / 93,000 miles