Synthetic aircraft turbine oil

A synthetic lubricating oil composition comprising a major portion of an aliphatic ester base oil having lubricating properties formed from the reactions of a pentaerythritol or trimethylolpropane and a saturated hydrocarbyl monocarboxylic acid having from about 2 to 18 carbon atoms per molecule, containing

• A. from about 0.01 to 0.5 weight percent of a substituted 4-aminotriazole represented by the formula:
• ##STR10## in which Y is a hydrocarbylidene radical or hydroxy-substituted hydrocarbylidene radical having from 8 to 18 carbon atoms,
• B. from about 0.3 to 5 percent by weight of the lubricating oil composition of an alkyl or alkarylphenyl naphthylamine represented by the formula:
• ##STR11## in which R is an alkyl or alkaryl radical having from about 4 to 12 carbon atoms,
• C. from about 0.3 to 5 percent of a dialkyldiphenylamine in which the alkyl radicals have from 4 to 12 carbon atoms, and
• D. from about 0.25 to 10 percent of a trihydrocarbyl phosphate in which said hydrocarbyl radical contains an aryl ring and contains from about 6 to 18 carbon atoms.

A synthetic lubricating oil composition comprising a major portion of an aliphatic ester base oil having lubricating properties formed from the reaction of a pentaerythritol or trimethylolpropane and a saturated hydrocarbyl monocarboxylic acid having from about 2 to 18 carbon atoms per molecule, containing

• A. from about 0.01 to 0.5 weight percent of a substituted 4-aminotriazole represented by the formula:
• ##STR12## in which R is hydrogen or an aliphatic hydrocarbon radical having from 1 to 4 carbon atoms,
• B. from about 0.3 to 5 percent by weight of the lubricating oil composition of an alkyl or alkarylphenyl naphthylamine represented by the formula:
• ##STR13## in which R is an alkyl or alkaryl radical having from about 4 to 12 carbon atoms,
• C. from about 0.3 to 5 percent of a dialkyldiphenyamine in which the alkyl radicals have from 4 to 12 carbon atoms, and
• D. from about 0.25 to 10 percent of a trihydrocarbyl phosphate in which said hydrocarbyl radical contains an aryl ring and contains from about 6 to 18 carbon atoms.

A synthetic lubricating oil composition comprising a major portion of an aliphatic ester base oil having lubricating properties formed from the reaction of a pentaerythritol or trimethylolpropane and a saturated hydrocarbyl monocarboxylic acid having from about 2 to 18 carbon atoms per molecule, containing

• A. from about 0.01 to 0.5 weight percent of a substituted 4-aminotriazole represented by the formula:
• ##STR14## in which R is hydrogen or an aliphatic hydrocarbon radical having from 1 to 4 carbon atoms R'" is an alkylene radical having from 2 to 18 carbon atoms,
• B. from about 0.3 to 5 percent by weight of the lubricating oil composition of an alkyl or alkarylphenyl naphthylamine represented by the formula:
• ##STR15## in which R is an alkyl or alkaryl radical having from about 4 to 12 carbon atoms,
• C. from about 0.3 to 5 percent of dialkyldiphenyamine in which the alkyl radicals have from 4 to 12 carbon atoms, and
• D. from about 0.25 to 10 percent of a trihydrocarbyl phosphate in which said hydrocarbyl radical contains an aryl ring and contains from about 6 to 18 carbon atoms.

A synthetic lubricating oil composition comprising a major portion of an aliphatic ester base oil having lubricating properties formed from the reaction of a pentaerythritol or trimethylolpropane and a saturated hydrocarbyl monocarboxylic acid having from about 2 to 18 carbon atoms per molecule, containing

• A. from about 0.01 to 0.5 weight percent of N-salicylidene-4-amino-1,2,4-triazole,
• B. from about 0.3 to 5 percent by weight of the lubricating oil composition of an alkyl or alkarylphenyl naphthylamine represented by the formula:
• ##STR16## in which R is an alkyl or alkaryl radical having from about 4 to 12 carbon atoms,
• C. from about 0.3 to 5 percent of a dialkyldiphenyamine in which the alkyl radicals have from 4 to 12 carbon atoms, and
• D. from about 0.25 to 10 percent of a trihydrocarbyl phosphate in which said hydrocarbyl radical contains an aryl ring and contains from about 6 to 18 carbon atoms.

A synthetic lubricating oil composition comprising a major portion of an aliphatic ester base oil having lubricating properties formed from the reaction of a pentaerythritol or trimethylolpropane and a saturated hydrocarbyl monocarboxylic acid having from about 2 to 18 carbon atoms per molecule, containing

• A. from about 0.01 to 0.5 weight percent of N-benzylidene-4-amino-1,2,4,-triazole,
• B. from about 0.3 to 5 percent by weight of the lubricating oil composition of an alkyl or alkarylphenyl naphthylamine represented by the formula:
• ##STR17## in which R is an alkyl or alkaryl radical having from about 4 to 12 carbon atoms,
• C. from about 0.3 to 5 percent of a dialkyldiphenylamine in which the alkyl radical have from 4 to 12 carbon atoms, and
• D. from about 0.25 to 10 percent of a trihydrocarbyl phosphate in which said hydrocarbyl radical contains an aryl ring and contains from about 6 to 18 carbon atoms.

A synthetic lubricating oil composition comprising a major portion of an aliphatic ester base oil having lubricating properties formed from the reaction of a pentaerythritol or trimethylolpropane and a saturated hydrocarbyl monocarboxylic acid having from about 2 to 18 carbon atoms per molecule, containing

• A. from about 0.01 to 0.5 weight percent of N-dodecylidene-4-amino-1,2,4-triazole,
• B. from about 0.3 to 5 percent by weight of the lubricating oil composition of an alkyl or alkarylphenyl naphthylamine represented by the formula:
• ##STR18## in which R is an alkyl or alkaryl radical having from about 4 to 12 carbon atoms,
• C. from about 0.3 to 5 percent of a dialkyldiphenyamine in which the alkyl radicals have from 4 to 12 carbon atoms, and
• D. from about 0.25 to 10 percent of a trihydrocarbyl phosphate in which said hydrocarbyl radical contains an aryl ring and contains from about 6 to 18 carbon atoms.

A synthetic lubricating oil composition consisting of 90 to 98 percent of an aliphatic ester base oil having lubricating properties formed from the reaction of a pentaerythritol or trimethylolpropane and a saturated hydrocarbyl monocarboxylic acid having from about 2 to 18 carbon atoms per molecule, containing

• A. from about 0.01 to 0.5 weight percent of a substituted 4-aminotriazole represented by a formula selected from the group consisting of:
• ##STR19## d. The amine salt of (c) in which the amine is a primary monoamine represented by the formula:
• R""NH.sub.2
• in which Y is a hydrocarbylidene radical or hydroxy-substituted hydrocarbylidene radical having from 8 to 18 carbon atoms, R is hydrogen or an aliphatic hydrocarbon radical having from 1 to 4 carbon atoms R'" is an alkylene radical having from 2 to 18 carbon atoms, and R"" is an aliphatic hydrocarbon radical having from 1 to 18 carbon atoms
• B. from about 0.3 to 5 percent by weight of the lubricating oil composition of an alkyl or alkarylphenyl naphthylamine represented by the formula:
• ##STR20## in which R is an alkyl or alkaryl radical having from about 4 to 12 carbon atoms,
• C. from about 0.3 to 5 percent of a dialkyldiphenyamine in which the alkyl radicals have from 4 to 12 carbon atoms, and
• D. from about 0.25 to 10 percent of a trihydrocarbyl phosphate in which said hydrocarbyl radical contains an aryl ring and contains from about 6 to 18 carbon atoms.