The rheological and tribological performance of a series of greases blended with and without an OCP based polymeric additive will be presented. In all, five fully blended Li-complex based greases were tested in this work. A tapered thrust bearing, KRL, rig was used for all the grease tribological tests. These tests were then followed by optical analysis on the roller large-ends to identify the failure modes. Two rheological parameters, G' and η*, were selected and recorded at 25°C, 40°C and 100°C to approximate bearing operating temperatures. These parameters were then correlated with the bearing and optical results. Finally, a performance rating based on grease operating temperature and supported with corroborative evidence form the previous techniques was derived.