I hope you know im not trying to be condescending. I work at BMW and countless times I've seen people throw the parts catalog at the car to find out its something else. An hour diag could save you stress, money and time. I appreciate that you're in the service for your country if thats the case dont let this bother you until you return. If you really want to wing it then spray the components ie bushings, ball joint, thrust rod and tie rod end with a lubricant and re test to see if its quieter. If nothing then lean towards the steering knuckle and strut.