Patent ID: 7910526

Claim:
A grease composition for use in constant velocity joints, comprising the following components (a) to (g): (a) a base oil; (b) a diurea thickener represented by the following general formula: R 1 NH—CO—NH—C 6 H 4 -p-CH 2 -C 6 H 4 -p-NH—CO—NHR 2 wherein R l and R 2 each independently represents an alkyl group having 8 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms or a cycloalkyl group having 6 to 12 carbon atoms; (c) a molybdenum dialkyl dithiocarbamate insoluble in the base oil; (d) a molybdenum dialkyl dithiocarbamate soluble in the base oil; (e) molybdenum disulfide; (f) calcium phenate; and (g) a sulfur-containing extreme-pressure agent free of phosphorus, wherein the content of the component (b) ranges from 2 to 20% by mass, that of the component (c) ranges from 0.5 to 5% by mass, that of the component (d) ranges from 0.5 to 5% by mass, that of the component (e) ranges from 0.5 to 5% by mass, that of the component (f) ranges from 0.5 to 5% by mass, and that of the component (g) ranges from 0.5 to 5% by mass, on the basis of the total mass of the grease composition, and wherein a mixing ratio of the oil-insoluble component (c) to the oil-soluble component (d) ranges from 20:80 to 40:60 as expressed in terms of the mass ratio.