IN A PROCESS FOR THE SEPARATION AND REMOVAL OF WAX FROM PETROLEUM HYDROGACBON OILS SUCH AS DISTILLATES, RESIDUAL BRIGHT STOCKS AND THE LIKE, BY DISSOLVING THE OIL IN A DEWAXING SOLVENT OR MIXTURE OF SLVENTS, CHILLING THE SOLUTION TO CRYSTALLIZE OR PRECIPITATE THE WAX, SEPARATING THE EDWXED OIL SOLUTION FROM THE WAX AS BY CENTRIFUGATION OR FILTRATION AND RECOVERING A SOLVENT-FREEE OIL AND WAX, THE IMPROVEMENT COMPRISING: THE INCORPORATION INTO THE OIL OR OIL-SOLVENT MIXTURE PRIOR TO OR DURING THE CHILLING OPERATION OF A MIXTURE OF: (A) AT LEAST TWO DIFFERENT ZIEGLER-NATTA CATALYZED LONG CHAIN OLEFINS HOMOPOLYMERS, OR AN INTERPOLYMER COMPRISING AT LEAST TWO DIFFERENT LONG CHAINS OLEFINS, SAID OLEFINS BEING C14 TO C24 "SUBSTANTAILLY LINEAR" ALPHA-MONO-OLEFINS OR MIXTURES THEREOF AND (B) A HOMOPOLYMER OR INTERPOLYMER OF ONE OR MORE C10 TO C24 N-ALKYL ESTERS OF METHACRYLIC ACID. USE OF THE MIXTURE OF THE DEWAXING AIDS (A) AND (B) CAN RESULT IN THE FORMATION OF A WAX CRYSTAL THAT FILTERS MORE RAPIDLY AND RETAINS LESS OIL THAN WHEN EITHER COMPONENT OF THE MIXTURE IS USED ALONE AT COMPATABLE CONCENTRATIONS.