how it works

In a standard, conventional, Subaru Automatic transmission the ‘Input shaft gear’ and the ‘Out put shaft gear’ make contact with each other as shown in figure 1 below.

Figure 2 below, shows the ‘transfer gear plate’. This plate is installed into the Output shaft bearing bore in the Subaru automatic transmission and then fastened to the transmission by way of 2x M8 high tensile bolts which screw into the threads of the ‘Parking pawl taper block’. The ‘Transfer gear plate’ allows a third gear (the ‘Transfer gear’) to be installed into the Subaru automatic transmission.

As shown in figure 3 below the transfer gear (middle gear) attaches to the ‘Transfer gear plate’ by way of 2x tapered roller bearings which are retained by an ‘R type’ locking nut. In addition to this, to allow for the thickness of the ‘Transfer gear plate’ being inserted into the original bearing bore, there is an undersized bearing installed to the rear of the output gear which is fastened to the gear by way of a 40mm external circlip.  

NOTE: The red arrow in figure 4 is pointing to the ‘Transfer gear plate’. 

Figure 3

The third gear, now known as the ‘Transfer gear’, is positioned between the Input shaft gear and the Output shaft gear and makes contact with both of the above mentioned gears. As shown in figure 4 below. 

Figure 4

The third gear (Transfer gear) causes the Output shaft (differential pinion) to rotate the same direction as the input shaft. This achieving a ‘reverse drive’ which allows the transmission to be installed and utilised in a vehicle which has a ‘rear mounted engine’, such as a 70’s or 80's model Volkswagen Kombi / bus or beetle or Porsche.   

'TRANSFER GEAR PLATE' PATENT PENDING: 2023900249