| abstract |
Lubricating compositions comprising a major proportion of lubricating oil and a minor proportion of at least one additive of the formula: n n Y.sup.a --S--Y.sup.b n n wherein Y a corresponds to ##STR1## and Z is ##STR2## and each R 1 and R 2 is independently hydrocarbyl, hydrocarbyloxy and hydrocarbylmercapto of one to about 30 carbon atoms; R 3 is hydrogen or hydrocarbyl of up to about 10 carbon atoms; R 4 is hydrogen or lower alkyl; R 5 and R 6 are each independently hydrogen, hydrocarbyl, hydrocarbyloxy and hydrocarbylmercapto of one to about 10 carbon atoms; R 7 is hydrogen or hydrocarbyl of one to about 30 carbon atoms; each X is independently oxygen or divalent sulfur; n is zero or an integer of one to about 10; n' is zero or an integer of one to about 9; Y b is n n --R.sup.8 --H or --R.sup.8 --S--R.sup.9 n n wherein R 8 is a divalent hydrocarbyl group of one to about 30 carbon atoms and R 9 is hydrogen or Y a have increased resistance to oxidative degradation and anti-wear properties. |