Valve stems seals is usually the 4.8.

The only thing we can be sure of is our personal experience. If we use the forum to draw conclusions we are using a small sample of the world of E53s, the majority here because of issues. There have been times when I considered not coming to the forum because I found myself worrying about taking my X5 out of the garage from reading all the negative posts.

I am not saluting the BMW flag, certainly not making excuses. I relate my experience so both sides of the coin are represented and in this case because I have a 4.6. I also think it is easy to read about problems and come to believe all are chronic, happen to all years and all engines. I respect your opinion I just don't share it. Certainly OP should gather info if not already aware of both the pluses and minuses. I just happen to be on the plus side where few weigh in.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas