Need help with Thump and DSC malfunction.

[X5prostock]

Hello.
Cool Website. Looks like a lot of cool folks on here too. I am new BMW owner. Actually the wife is. I just get to keep it going and safe. 2012 X5 (premium?)
E70 (i believe) I35 Xdrive. 40K miles.

So I am driving along and it thumps from underneath, goes in to limp mode and puts up some error codes. It has done it 4 times now. Each time I can pull over (if alive) and turn it off, wait a few seconds, and start it up, and drive it like I stole it. All codes clear.

The codes are..
DSC malfunction, DBC malfunction, Chassis Stabilization malfunction.
The 4x4 indicator, check engine light, half motor light (limp mode), come on.
Not all this at the same time. The thump and power loss are generally associated with the DBC malfunction.
Just had water pump, themostat, thermostat housing and bolts replaced.
Changed battery to new one. Old one load tested good after I got it out.

I see stuff about bad transfer cases, short drive shafts, corroded speed sensors, calibration of steering sensors, ect. How do I nail this down? It does feel to me like it decouples the rear wheels (thump), then turns on the front wheels and reduces power just so it will limp along. Transfer case?

Any help or links are super appreciated.

Thanks

[heatmizr]

Jesus you guys are scaring me...
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