Lubricating oil compositions and use thereof for improving journal bearing durability in internal combustion engines

A method of decreasing journal bearing wear in an internal combustion engine comprising:

• providing to the internal combustion engine a lubricating oil composition comprising:
• an oil of lubricating viscosity at greater than 75 wt. % of the composition comprising a Group I base oil, a Group II base oil, a Group III base oil, a Group IV base oil, or combinations thereof;
• one or more overbased metal based detergents with a Total Base Number (KOH/g) greater than or equal to 9 and less than or equal to 500 and at treat level to deliver between 1000 to 2000 ppm by weight of metal to the composition;
• and
• a friction modifier comprising glycerol monooleate at from 0.2 to 0.7 wt. % of the composition;
• the lubricating oil composition having a total sulfated ash of less than or equal to 1.0 wt. %, a high temperature high shear viscosity at 150° C. (HTHS) as determined according to ASTM D4683-20 of greater than or equal to 1.8 mPa·s and less than or equal to 2.9 mPa·s, and a total phosphorous level of less than or equal to 0.080 wt. %, and
• wherein the lubricating oil composition provides a 10% to 80% decrease in journal bearing wear as measured by wear scar volume in μm3 using the MTM-R test method compared to a lubricating oil composition of comparable HTHS, but not including a friction modifier comprising glycerol monooleate at from 0.2 to 0.7 wt. % of the composition, and
• wherein a shell material of the journal bearing is a non-ferrous material selected from the group consisting of a bimetal, a trimaterial/metal and a solid material.

A method of making a lubricating oil composition comprising combining:

• (i) an oil of lubricating viscosity at greater than 75 wt. % of the composition comprising a Group I base oil, a Group II base oil, a Group III base oil, a Group IV base oil, or combinations thereof;
• (ii) one or more overbased metal based detergents with a Total Base Number (KOH/g) greater than or equal to 9 and less than or equal to 500 and at treat level to deliver between 1000 to 2000 ppm by weight of metal to the composition;
• and
• (iii) a friction modifier comprising glycerol monooleate at from 0.2 to 0.7 wt. % of the composition;
• the lubricating oil composition having a total sulfated ash of less than or equal to 1.0 wt. %, a high temperature high shear viscosity at 150° C. (HTHS) as determined according to ASTM D4683-20 of greater than or equal to 1.8 mPa·s and less than or equal to 2.9 mPa·s, and a total phosphorous level of less than or equal to 0.080 wt. %, and
• wherein the lubricating oil composition provides a 10% to 80% decrease in journal bearing wear as measured by wear scar volume in μm3 using the MTM-R test method compared to a lubricating oil composition of comparable HTHS, but not including a friction modifier comprising glycerol monooleate at from 0.2 to 0.7 wt. % of the composition, and
• wherein a shell material of the journal bearing is a non-ferrous material selected from the group consisting of a bimetal, a trimaterial/metal and a solid material.