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.