745 & 740 GC Articulated Truck Caterpillar

Illustration 1	g06198691
Location of transmission oil filter is left the side under the cab. (1A) Filter base (1B) Filter element housing (2) Bypass valve (3) Pressure test port (4) Bypass switch (5) SOS sample port

The transmission oil filter is located under the left rear section of the operator station.

The transmission oil filter base contains S-O-S test port (5) that is used to collect oil samples from the transmission oil system. The filter base also contains filter bypass valve (2). If the filter becomes impregnated with contaminants, the pressure on the bypass valve will increase. When the pressure differential between the filter inlet and outlet is greater than 724 kPa (105 psi), the bypass valve will open.

Normally Closed bypass switch (4) will open at the same pressure of 724 kPa (105 psi). The opened switch will send a signal to the transmission ECM. The transmission ECM shares this data with the secondary display, which warns the operator of a "Filter Clogged" condition.

Pressure test port (3) is also contained in the filter base. This test port can be used to test the transmission pump supply pressure to the transmission hydraulic control manifold.

The S-O-S port is installed in the inlet to the filter. The pressure test port is installed in the outlet from the filter.