Thanks for all your replies. I will pay attention for the diesel "clatter" when I drive it. I am actually looking at a 2010 model with 3.5 years and 55,000 miles left on the certified pre-owned warranty, so I feel fairly comfortable with that protection. Although this particular X5 would have a warranty, I still want to be aware of any common issues or diesel specific quirks.

Just so I know what to expect when I test drive it, are we talking cut the engine off at drive thru clatter (aka Ford F250 diesels) or just louder than a normal BMW engine clatter? I am assuming the latter.

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