5 speed to 6 speed swap?

[paramax55]

I'm still trying to decide what I want to do with my 2001 5-speed that needs a head gasket. Part of my decision making has been parusing marketplace for a replacement car. But that sparked a curious question - what if "while I'm in there" I upgrade to a 6-speed tranny? Is the 6-speed longer? Will my AWD transfer case bolt in place of the 4WD transfer case offered on the later models? If it's longer, is the stickshift in the same place? Driveshaft changes are almost trivial. Currently, it's just a thought experiment.

[Effduration]

https://xoutpost.com/bmw-sav-forums/...peed-swap.html

and this:
https://xoutpost.com/bmw-sav-forums/...ted-slips.html

Looks like a front AND rear diff swap - they have to match of course- is what you should consider

[paramax55]

I did a diff swap on my e30. It was quick and easy. If I were going ti do that in this car, the time to do it would be while the intake isn't in the way. But I do like the low 1st gear for clutch longevity. Pulling a transmission just because the clutch plate is worn really sucks.

The first thread was talking about using an e46 transmission, which mates differently to the transfer case. It would need to be an e53 transmission I guess, and I still don't know if that would mate up or not.

I guess my question really comes down to the length of the transmission and whether the transfer case swaps - mainly the transfer case.