I have replaced subframe bushings. There are several how to's and I have also seen a youtube video. I wouldn't even think of tackling that job without the special tool.

If the rest of the front and rear suspension has the same miles as the sub frame bushings they should be checked thoroughly when the sub frame bushings are done.

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