Subject: E30 transmission guide
To: dale
Firstly, all 'i' motors use a crank position sensor on the front of the crank, all 'eta' motors (super-eta may be an exception) use the 2 reference sensors mounted in the trans bellhousing.
There are a couple of issues using an '86 325e manual transmission in an '89 325i car.
Identify which trans you have early 'eta', late 'eta', or 'i':
- early 'eta' trans (1983, 1984, 1985 manufacture dates?)
- 260.0.1270.90 is on the side of the 'eta' trans
- shifter mounting about the output flange is only 2xM10 holes for the 84,85,86 style plate mount shifter
- deep bellhousing : Slave cylinder mounting flange = 6 7/8
- 2 drilled holes for crank position sensors
- smaller output flange
b) late 'eta' trans (1986, 1987, 1988 manufacture dates?)
- 260.0.1270.90 is on the side of the 'eta' trans
- shifter mounting about the output flange has 2xM10 holes for the 84,85,86 style plate mount shifter, AND top boss for the aluminum bracket of the 87-91 style shifting mechanism.
- shallow bellhousing : Slave cylinder mounting flange = 6 1/2
- cast boss for 2 drilled holes for crank position sensors, may or may not be drilled
- larger output flange
c) 'i' trans
- 260.0.1346.90 is on the side of the 'i' trans
- top boss for the aluminum bracket of the 87-91 style shifting mechanism.
- shallow bellhousing : Slave cylinder mounting flange = 6 1/2
- no cast boss in bellhousing for reference sensors
- smaller output flange
If you find your 'eta' 260 trans has the deeper bellhousing, you can correct for it by using a thicker throw-out bearing.
Sachs P/N 21511204525 is a 30mm bearing and will make up the difference.
If you use the driveshaft/guibo that came with the transmission you'll be fine, the differential end of the driveshaft is the same on all the 6cyl E30s.