Many people have either added a longer spline end to their existing prop shaft or bought the two piece kits that is designed for easy install.

About 8:1 ratio I've witnessed do not need to replace the TC (or the gear inside that mates with the prop).

(BMW refers to the front drive shaft as the front propeller shaft at least some of the time). I prefer to use the term vs. drive shaft to exclude confusion with the CV axles which are also often called drive shafts or half shafts.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)