Insert the intermediate shaft into the rear cover of the gearbox housing and measure the depth of the rear cover, i.e. the distance between the mating surface of the rear cover (with installed gasket) and the retaining ring of the front bearing of the intermediate shaft (see photo).
Notes: If the intermediate shaft rear bearing remains in the transmission housing rear cover seat (due to strong tension on the outer ring of the bearing when pressed into the socket), heat the rear cover to facilitate pressing out the bearing, without exceeding a temperature of 80-100X.
Both measured dimensions: the depth of the gearbox housing rear cover and the length of the intermediate shaft gear block must be the same. If they are different, the difference between them will be equal to the thickness of the adjusting rings installed on the intermediate shaft front bearing. If the total thickness of the adjusting rings reaches or exceeds 0.4 mm, install adjusting rings of equal thickness at both ends of the shaft to ensure the correct relative position of the intermediate, secondary and primary shaft gears. In this case, heat the gearbox housing rear cover to a temperature of 80-100°C, ensuring that the burner flame does not touch the plastic driven gear of the speedometer drive, and install half of the adjusting rings under the intermediate shaft rear bearing.
The original entry can be found on the portal BMWMan