Abstract: Functional fluids characterized as effective over a wide range of temperature including very high temperatures can be prepared, comprising:(A) a major amount of at least one synthetic base oil; and minor amount of(B) at least one phenolic compound selected from the group consisting of(B-1) metal-free, hindered phenols substituted with at least one alkyl group containing at lease about 6 carbon atoms, and alkylene coupled derivatives thereof;(B-2) neutral and basic alkaline earth metal salts of hindered phenols which are not alkylene or sulfur-coupled;(B-3) metal-free alkyl phenol sulfides or neutral and basic alkaline earth metal salts of alkyl phenol sulfides; and(B-4) neutral and basic alkaline earth metal salts of alkylene-coupled phenols; and(C) at least one non-phenolic antioxidant.

Abstract: Normally liquid fuel compositions containing N-substituted morpholines of the formula ##STR1## wherein R' is a divalent organic radical of at least one to about 30 carbon atoms, R.sup.3 is a hydrogen atom or a hydrocarbyl, a hydroxy-substituted hydrocarbyl or a hydroxy hydrocarbyleneoxy-substituted hydrocarbyl radical of at least one carbon atom and R" is a monovalent hydrocarbon radical of at least thirty carbon atoms, exhibit improved carburetor detergency and anti-icing properties. These fuels also inhibit deposit formation in the intake systems of internal combustion engines. Particularly preferred are gasolines containing morpholines wherein R' is 1,3-propylene, or poly(ethyleneoxy), R" is a hydrocarbyl group of at least about forty carbon atoms and R.sup.3 is hydrogen.