I originally bought the manual-shift 240D as a parts-car, because I was considering converting my nicer-looking automatic 240D to a manual. Also my automatic 240D was experiencing low oil-pressure problems, so I was considering swapping engines as well. However the automatic car's oil-pressure problem seems to have subsided, and the 4-speed car runs so well that I decided to go ahead and repair it's floors and keep it as a second car at my parents home in Virginia Beach.
As for swapping the rear-end, it would be a relatively easy change. I actually have a spare 240D manual tranny, but a conversion would still be a major project, requiring a donor-car to supply flywheel, driveshaft, shifter, clutch hydraulics and pedal assembly, with all the extra labor. And If I decided the 2.46 rear wasn't up to my expectations, it would be relatively easy to change back. Besides, If I get the 300D parts-car for free, there's the potential to upgrade engines and make mine a 240D-3.0, while retaining the manual heat/AC which was one of the things that drew me to the 240D in the first placce.

Happy Motoring, Mark

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DrDKW