1. The antiwear properties of lithium greases without additives line up with those of the dispersion media, in the following order from poorest to best: PES-3 silicone, MS-6 mineral oil, DOS (dioctyl sebacate). 2. The replacement of lithium stearate by lithium soaps of synthetic fatty acids gives lithium greases with poorer antiwear properties. 3. When thickener is added to the oils, they all tend to be about the same in extreme-pressure properties. 209 4. Feasibility has been demonstrated for improving the lubricity of greases by treatment of the petroleum-oil dispersion media and by blending media that differ in chemical nature.