4 spd VS 5 spd parts

[nbean01]

Hello! I have a '78 e21 320i auto. I'm doing a manual swap. I just got a 5 speed out of a different e21. I found a parts car, but its a 4 speed. How many of the transmission parts are interchangeable? Driveshafts, trans mount, etc. Any info is greatly appreciated! Thank you!

[ascot]

You will need the driveshaft from a five speed car. You will also need to determine the model year of the car that your five speed came from. Model year 80 used a four bolt output flange while the 81-83 models used a three bolt output flange. The 83 model also used a driveshaft that is longer than the driveshaft used on the 80-82 models. Also if your five speed is from an 83 model the shift platform and linkage are different from the 80-82 models.

[320iAman]

As Ascot said with 80-82 are Getrag 245 5 sp, 83 is Getrag 240 5 Sp. The Getrag 245's come with steel shift forks while Getrag 240 are aluminum shift forks, steel shift forks are more desirable for the higher output motor shifting in that they are stronger. 245's are usually 2x-3x the price of 240's.

Randy