Outboard gear oil

Outboard gear oil is located in the lower unit. It lubricates the gears used for shifting and driving the propeller.

The gear oil should be changed annually. This also lets you check whether water has entered the oil. Although the system is sealed, the lower unit is submerged while boating. Water reduces the oil’s lubricating properties and may damage the gears. Moisture can enter the gearcase even with limited use, so changing the oil remains important.