Abstract: Disclosed herein is lubricating oil composition for providing enhanced piston cleanliness in an internal combustion engine. The lubricating oil composition includes (a) greater than 65 wt. %, based on the total weight of the lubricating oil composition, of a base oil component having a Kv at 100° C. of about 3.5 to about 4.5 cSt; (b) about 3.0 wt. % to about 10 wt. %, based on the total weight of the lubricating oil composition, of at least one Mannich reaction product prepared by the condensation of a polyisobutyl-substituted hydroxyaromatic compound, wherein the polyisobutyl group is derived from polyisobutene containing at least about 70 wt. % methylvinylidene isomer and has a number average molecular weight of from about 400 to about 2,500, an aldehyde, an amino acid or ester derivative thereof, and an alkali metal base; and (c) at least one ashless dispersant other than component (b); wherein the lubricating oil composition has a sulfur content of less than or equal to about 0.30 wt.

Abstract: Disclosed herein is lubricating oil composition for providing enhanced piston cleanliness in an internal combustion engine. The lubricating oil composition include (a) from about 50 to about 65 wt. %, based on the total weight of the lubricating oil composition, of a first base oil component having a Kv at 100° C. of about 3.5 to about 4.5 cSt; (b) from about 10 to about 30 wt. %, based on the total weight of the lubricating oil composition, of a second base oil component having a Kv at 100° C. of about 5.5 to about 6.5 cSt; (c) about 1.50 wt. % to about 10 wt. %, based on the total weight of the lubricating oil composition, of at least one Mannich reaction product as disclosed herein; and (d) at least one ashless dispersant other than component (c); wherein the lubricating oil composition has a sulfur content of less than or equal to about 0.30 wt. %, a phosphorus content of less than or equal to about 0.09 wt. %, and a sulfated ash content of less than or equal to about 1.60 wt.

Abstract: Disclosed herein is lubricating oil composition for providing enhanced piston cleanliness in an internal combustion engine. The lubricating oil composition include (a) from about 50 to about 65 wt. %, based on the total weight of the lubricating oil composition, of a first base oil component having a Kv at 100° C. of about 3.5 to about 4.5 cSt; (b) from about 10 to about 30 wt. %, based on the total weight of the lubricating oil composition, of a second base oil component having a Kv at 100° C. of about 5.5 to about 6.5 cSt; (c) about 1.50 wt. % to about 10 wt. %, based on the total weight of the lubricating oil composition, of at least one Mannich reaction product as disclosed herein; and (d) at least one ashless dispersant other than component (c); wherein the lubricating oil composition has a sulfur content of less than or equal to about 0.30 wt. %, a phosphorus content of less than or equal to about 0.09 wt. %, and a sulfated ash content of less than or equal to about 1.60 wt.