One of the challenges in lubricant development is to adequately model performance across a broad range of potential lubrication and wear regimes that are encountered in use. Since wear in a given application is dependent on both rolling and sliding speeds, it is desirable to determine lubricant performance as a function of these variables. The use of a new test machine and methodology permits the construction of performance maps which define the transitions between lubrication regimes - hydrodynamic/elastohydrodynamic (EHD), EHD/mixed film and mixed film/boundary. This paper describes a method of mapping out the performance of a lubricant over a range of rolling and sliding velocities. Lubrication and wear performance is characterized for an ester base reference fluid (Herco-A) and two commercially available gear oils based on a petroleum oil and a poly(alpha olefin).