A lubricant composition of a grade according to the SAEJ300 classification defined by the formula W wherein ▪ X represents 0 or 5; ▪ Y represents an integer ranging from 4 to 20; and comprising (a) at least one polyalphaolefinic oil for which the cinematic viscosity measured at 100 C according to the ASTM D445 standard ranges from 1.5 to 8 mm 2.s -1; (b) from 10 to 80% by weight of the composition of at least one oil of group V for which the cinematic viscosity measured at 100 °C according to the ASTM D445 standard ranges from 1.5 to 8 mm 2.s -1 selected from among: ▪ a monoester of formula; wherein o R 1 represents a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 14 to 24 carbon atoms; o R 2 represents a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 2 to 18 carbon atoms; ▪ a polyalkylene-glycol of formula wherein o R3 represents a linear or branched C1-C30-alkyl group; o m and n represent independently an average number ranging from 1 to 5; (c) at least one comb polymer for which the three pendant chains comprise at least 50 carbon atoms and selected from among the copolymers of at least one polyolefin and of at least one poly(alkyl)methacrylate; the copolymers of at least one polyolefin and of at least one poly(alkyl)acrylate. ▪ X represents 0 or 5; ▪ Y represents an integer ranging from 4 to 20; and (a) at least one polyalphaolefinic oil for which the cinematic viscosity measured at 100 C according to the ASTM D445 standard ranges from 1.5 to 8 mm 2.s -1; (b) from 10 to 80% by weight of the composition of at least one oil of group V for which the cinematic viscosity measured at 100 °C according to the ASTM D445 standard ranges from 1.5 to 8 mm 2.s -1 selected from among: ▪ a monoester of formula; wherein o R 1 represents a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 14 to 24 carbon atoms; o R 2 represents a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 2 to 18 carbon atoms; ▪ a polyalkylene-glycol of formula wherein o R3 represents a linear or branched C1-C30-alkyl group; o m and n represent independently an average number ranging from 1 to 5; ▪ a monoester of formula; wherein o R 1 represents a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 14 to 24 carbon atoms; o R 2 represents a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 2 to 18 carbon atoms; o R 1 represents a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 14 to 24 carbon atoms; o R 2 represents a linear or branched, saturated or unsaturated hydrocarbon group, comprising from 2 to 18 carbon atoms; ▪ a polyalkylene-glycol of formula wherein o R3 represents a linear or branched C1-C30-alkyl group; o m and n represent independently an average number ranging from 1 to 5; o R3 represents a linear or branched C1-C30-alkyl group; o m and n represent independently an average number ranging from 1 to 5; (c) at least one comb polymer for which the three pendant chains comprise at least 50 carbon atoms and selected from among the copolymers of at least one polyolefin and of at least one poly(alkyl)methacrylate; the copolymers of at least one polyolefin and of at least one poly(alkyl)acrylate.