Hard to get a sense of the severity of the shaking without being there. I suppose thrust arm bushings could cause your symptoms but would not say that is a sure thing. I think my first step would be to inspect the entire front suspension. Life of most suspension components are not all that dissimilar. Since you only have the symptoms from 40-60 I would also verify the tires are balanced. Symptoms like this could even be driveline related.

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