did the TSIB work help resolve the issue for you or was it something else that seems like the culprit

 

The TSIB helped, but what really helped the most with body vibration was the replacement of the drive shaft, which is not called for in the TSIB. The TSIB only calls for indexing and choosing the best position, but since that did not resolve the body vibrations for my car, the drive shaft was replaced.

While the roof reinforcement that is part of the TSIB should help, its main role (as I understand it) is to reduce the drone noise that the TSIB describes (which I never had). It may help a bit on the vibration front, but in the end, I think the drive shaft is the culprit (i.e., it is the one thing that rotates). Ditto for the replacement of the rear suspension stops - the third item on that TSIB - it likely helped marginally, but did not resolve the body vibration.

I would suggest - as a starting point, so that you don't have to incur the expense of the TSIB - that your dealer look at your drive shaft more closely (plus u-joint, couplings, etc.) and also tackling any other TSIB steps that are external to the car (suspension stops) prior to taking the whole interior apart. The drive shaft angle on my car was way, way off. This is a manufacturing/assembly problem that my dealership had to submit a detailed report to Lexus about. Every bit in the TSIB helped, but it was ultimately this, which went beyond the TSIB, that was the biggest issue (with body vibration; steering vibration was a separate problem).