Patent ID: 8546311

Claim:
A method for lubricating a clutch-only automatic transmission component requiring lubrication, comprising: 1) in an automatic dual clutch transmission including dual wet clutches and a direct-shifting gearbox, in which the dual wet clutches and the direct-shifting gearbox have separate oil cycles, adding a dual wet clutch lubricating fluid to the oil cycle of the dual wet clutches but not to the oil cycle of the direct-shifting gearbox, said dual wet clutch lubricating fluid comprising: a) an oil of lubricating viscosity formulated with additive components comprising: i) at least one metal detergent; ii) at least one phosphorus-based wear preventative; iii) a phosphorylated and boronated dispersant different than the at least one phosphorus-based wear preventative; iv) a sulfurized extreme pressure agent; b) a ratio between the content (ppm) of the sulfur based on the total weight of the fluid composition and a content (ppm) of phosphorus based on the total weight of the fluid composition of about 1.2 (ppm/ppm); and c) a ratio between the content (ppm) of the sulfur based on the total weight of the fluid composition and a content (ppm) of boron based on the total weight of the fluid composition of about 2.5 (ppm/ppm); and 2) operating the dual wet clutches of the automatic dual clutch transmission that contains the fluid.