John Deere AT85174 Oil Pressure Switch

The AT85174 oil pressure switch is an engine-mounted sensor designed to monitor lubrication system pressure and activate warning indicators when pressure falls below safe thresholds. It installs directly into the engine block oil gallery port using a 1/8 inch NPT tapered pipe thread. The switch incorporates a single-pole single-throw electrical contact with a 1/4 inch spade terminal for harness connection. Rated for 12 volt DC systems, the component operates as a normally closed switch that opens at calibrated pressure setpoint. Housing is constructed from brass and steel with elastomeric seals for oil resistance. Overall length measures approximately 2.595 inches. This switch serves as a direct replacement for John Deere OEM part numbers across multiple tractor and construction equipment platforms.