This test method is designed to simulate the synergistic combinations of oil flow, temperature cycling, hot spots, and tribology that would typically be found in a gas turbine engine. The method is intended to quantitatively characterize changes in four basic oil properties that are brought about by exposure to the afore mentioned simulated turbine engine environment: the tendency of aviation lubricants to form coke deposits, viscosity changes, total acid number changes (TAN), and oil consumption.