swapping 7 speed s-tronic for 6 speed tiptronic

[Intesity]

Hi all newbie here, have an European 2011 Audi A4 Quattro it has the 7 speed S-tronic .
We don't have many mechanics down here that do know these tranny's .
too not make a long story, mine tranny is shot, had it rebuilt 2 times $ 2000 in parts and it still does not work, I have the Ross-tech programmer but it aborts because of safety, so before I junk this car, I want to ask what would I need to swap the 6 speed tiptronic in place of the 7-speed .
they readily available on ebay and one third the price of an S-tronic .
It does not matter to me how it shifts, I just need to get rid of this car.

[Smac770]

Replacing a transmission is going to require an immobilizer adaptation. So you're going to have to involve a dealership or suitably capable shop at some point.

An MY11 0B5 is going to have a spline shaft output on the rear of the trans. The 0B6 are all flange shaft output. So you'd need a new cardan shaft.

https://audi.7zap.com/en/usa/audi+a4...4q/2010-636/3/
So go through the mounting parts and support frame pages for the 0B5 vs the 0B6 and see what's different.

https://audi.7zap.com/en/usa/audi+a4.../5/521-521010/
That's the page for the cardan shaft

G0K = 0B1/0B3 6MT FWD
G0L = 0B2/0B4 6MT quattro
G0R = 0B6 6AT quattro
G1C = 0B5 7AT FWD
G1D = 0B5 7AT quattro
G1G = 0BK 8AT quattro

T41 = 3.0 TDI
TR2 = 3.2L FSI
TC6 = 3.0T FSI
TF6 = 1.8T Gen2 FSI
TG6 = 2.0T Gen2 FSI
TH3 = 2.0 TDI
TL6 = 2.0T Gen2 FSI flex fuel

[Intesity]

Smac770. what if I find a donor car, and buy the tranny driveshaft Ecu with wiring and the key ? if it its more involved then that I think I would pass .

[Smac770]

The immobilizer master is the J393 BCM2 in the right rear. So you'd need that, the ECM, the TCM, and the ESL (electronic steering lock) (I think so on the last one), but then also the keys. It'd be a lot easier to just pay the dealership the one hour labor to run the adaptation. You'd just have to tow the car there. That's a lot of work for something you're just trying to unload.