Hello, welcome to the forum!

4.6is are great, very powerful, and unique! Only problems that you should know are the timing chain guide/tensioners and the lower pipe coolant gasket tend to fail, both of these may require the actual engine to be removed from the vehicle to be easier to work on.

The timing chain guides/tensioner fix can be upwards of $4500 to fix, majority is labor.

Other than that, there are typical regular X5 issues that plague all X5 owners, such as air suspension problems (compressor, air bags, calibration), our axles are pretty weak, and the rear subframe bushings and front upper control arms bushings wear rather quickly.

There are permanent fixes to the common X5 problems when they do occur, and most of them are possible with DIY, but unfortunately I'm not mechanically inclined.

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