Methods are provided for upgrading the quality of an asphalt. The methods include mixing an asphalt feed with a cracking resistance additive that improves the low temperature properties of the asphalt while leaving the high temperature properties unchanged or minimally changed. The cracking resistance additive corresponds to a compound that is a liquid at both the low temperature performance grade for the asphalt and at mixing and/or storage temperature for the asphalt. Examples of compounds that, in an appropriate molecular weight range, are liquids across this broad temperature range include polyalphaolefins, alkylated naphthalenes, and organic esters.