A composition comprising a refrigerant and a lubricant is disclosed, wherein the refrigerant comprises (i) a fluorocarbon selected from the group consisting of R125, R134a, R32, R152a, R143a, R218 and mixtures thereof, and (ii) a hydrocarbon selected from the group consisting of propane, n-butane, isobutane, n-pentane, isopentane, dimethyl ether, and mixtures thereof; the lubricant comprises (iii) a hydrocarbon-based lubricant component; and (iv) a synthetic lubricant component; and the synthetic lubricant component is less than 30% by weight of the total lubricant. Also disclosed are methods of replacing refrigerants in refrigeration or air conditioning systems containing a refrigerant comprising a CFC or HCFC and a lubricant. The methods involve adding to the system (a) a replacement refrigerant comprising (i) a fluorocarbon selected from the group consisting of R125, R134a, R152a, R32, R143a, R218 and mixtures thereof, and (ii) a hydrocarbon selected from the group consisting of propane, n-butane, isobutane, n-pentane, isopentane, dimethyl ether, and mixtures thereof; and (b) a synthetic lubricant component; wherein after refrigerant replacement the synthetic lubricant component is less than 30% by weight of the total amount of lubricant in the system.