US 12,291,686 B2
Lubricating oil compositions for automatic transmissions
Koichi Kubo, Kanagawa (JP); Masami Fuchi, Makinohara (JP); Naoya Sasaki, Omaezaki (JP); Takahiro Nakagawa, Omaezaki (JP); and Satoshi Ohta, Omaezaki (JP)
Assigned to CHEVRON JAPAN LTD., Minato-Ku (JP)
Filed by CHEVRON JAPAN LTD., Minato-ku (JP)
Filed on Mar. 19, 2020, as Appl. No. 16/823,946.
Prior Publication US 2021/0292676 A1, Sep. 23, 2021
Int. Cl. C10M 133/44 (2006.01); C10M 135/36 (2006.01); C10M 137/08 (2006.01); C10N 20/02 (2006.01); C10N 30/06 (2006.01); C10N 30/12 (2006.01); C10N 40/04 (2006.01)
CPC C10M 133/44 (2013.01) [C10M 135/36 (2013.01); C10M 137/08 (2013.01); C10M 2215/223 (2013.01); C10M 2219/106 (2013.01); C10M 2223/043 (2013.01); C10M 2223/049 (2013.01); C10N 2020/02 (2013.01); C10N 2030/06 (2013.01); C10N 2030/12 (2013.01); C10N 2040/042 (2020.05)] 6 Claims
 
1. A lubricating oil composition for battery electrical vehicles (BEVs), hybrid vehicles (HVs) and plug-in hybrid vehicles (PHVs) with electric motors and/or generators comprising:
a. at least 50 wt. % of an oil of lubricating viscosity having a kinematic viscosity at 100° C. in a range of about 1.5 to about 20 mm 2/s;
b. total of 300 to 390 ppm of phosphorus from aryl phosphite, inorganic phosphoric acid, and alkyl phosphate amine salt;
c. a nitrogen-based corrosion inhibitor, wherein the total amount of nitrogen provided by the corrosion inhibitor to the lubricating oil composition is 40 to 100 ppm based on the weight of the lubricating oil composition, wherein the nitrogen-based corrosion inhibitor is alkylated benzotriazole compound or benzotriazole compound;
d. a sulfur EP additive, wherein the total amount of sulfur provided by the sulfur EP additive to the lubricating oil composition is 300 to 1050 ppm based of the weight of the lubricating oil composition, wherein the sulfur EP additive is branched dialkyl thiadiazole compound or linear dialkyl thiadiazole compound;
wherein the lubricating oil composition contains less than 50 ppm of metals and has a volume resistivity greater than 1.0×10 9 Ω·cm at 80° C.