Hi guys. I'm new to this forum, so don't pounce!
I have been running a 200Tdi in my 109 for nearly a year and it has not yet harmed the transmission in any apparent way. This includes a 2,500 mile trip to do the Alps this summer, where the vehicle had to run down the auto-routes at 70mph with a 3.5T gross weight and all the drag of the kit on the roof, as well as dragging that weight up to 10,500' to the Sommelier glacier, and several hundred miles off road. The only mods to the transmission were the Rocky Mountain overdrive and transfer box bottom plate, and the only trouble on the transmission was that the oil turned a bit darker, like caramelised sugar. That is due to the heat from working so hard at high weight behind a Tdi and using cheap Comma mineral oil. Other oil changes where the vehicle hasn't been worked unusually hard produce normal looking waste oil.
As for fitting the engine without the turbo, using the intercooler would not only have no positive influence, since the induction air is already at ambient temperature, but would actually slightly restrict the air, marginally hampering performance.
