Time to think through what you have done and your next step.

You have spent money that didn't fix anything. The majority of the time that means we jumped to judgment as to the cause when more troubleshooting was the thing to do. The way to see that is when the input shows there is little unity as to the cause.

As I understand you had no shake at all until you made the rim, tire and spacer change. I don't believe in coincidences. The odds on favorite core issue is that one of those components are still the culprit.

Road force balancing should have eliminated any problems associated with the tire and rim combination. Of course that assumes they were competent and were able to make any needed adjustments.

Since you have replaced the spacers and tires it is very reasonable to conclude they weren't the problem for now.

If the steering rack is the cause there should be other symptoms such as leaks, hesitation when you try to turn the steering wheel at an idle, kind of a squeal or rushing air sound when steering wheel is turned to lock point in one or both directions or steering wheel is harder to turn all the time. It is a very long shot that the change you made trashed the rack. I wouldn't have work done on the steering rack yet.

The motor mounts may need replacement but my experience with motor mount symptoms does not include shaking-- when you are experiencing it . And, it is a big stretch for me to believe that happened when you made the rim/tire/spacer change. They're easy to check if you want.

Generally, when one suspension component fails the best course of action is to inspect the entire suspension before replacing anything. One of the reasons is so it doesn't have to be disassembled more than once since more often than not the failure of one part signals the rest are close behind and the same symptoms can be caused by more than one component. It's fairly easy to change the wrong part. Off the top of my head, I can think of only a couple of reasons that could tie to the change. Suspension may need rebuilding but it is also very unlikely the problem. It is extremely rare it happens that way. One possible suspension problem because of the whee/tire change could be that a suspension load change pushed the failing part to a point beyond what was generated prior to the change so now there are symptoms that didn't show before. While possible I don't think likely and the failing part should show in the repair shop inspection.

If at all possible, return to the wheels, tires and rims before this started and see if it still shakes. If it doesn't, add only the spacers and see if the shake appears. If it doesn't put only the new wheels and tires on and see if it shakes. If it doesn't add the spacers. Depending on when the shake appears the troubleshooting has eliminated almost all of the possibilities.

If that is not possible the next thing I would do is verify the spacers and rims center on the hubs. Then I would have a recheck done of the road force balancing and have them show me on the screen or a printout that the rims and tires are not the problem.

Then I would have the repair shop show me the problem with each component on their estimate. Worn suspension parts are pretty obvious when demonstrated. What is the shop's reputation? As the only game in town they can easily be expensive but if they do good work it's a far better option than the 8 hour drive.

If this doesn't locate the core issue we will be, guessing, 90% of the way without buying any more parts you don't need.

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