The present invention relates to a system, method, and computer program product for monitoring oil condition. In one embodiment, a marine powertrain is provided that includes a marine engine and a gear casing containing an oil and a gas. An engine speed sensor generates an output value, which indicates a speed of the marine engine. An oil sensor generates an output value, which indicates a condition of the oil. The condition of the oil is selectively monitored according to whether the marine engine is operating at a speed that is less than an engine speed threshold value, which denotes a speed of the marine engine at which the oil and the gas form an oil and aerated gas mixture.