A fuel composition having an enhanced thermal stability in a diesel fuel application is provided comprising a base fuel containing: (a) 90 to 50% by volume based on the base fuel, of a petroleum refined diesel fuel having sulfur level of less than 500 ppm, and boiling point within the range of about 150 to about 400° C.; (b) 5 to 25% by volume based on the base fuel, a Fischer-Tropsch derived gas oil; and (c) 5 to 25% by volume based on the base fuel, a fatty acid alkyl ester having C18:2 to C18:1 ratio of 1.5 to 2.8 wherein the alkyl group has a carbon number from 1 to 4.