NOVELTY - A fuel composition comprises at least one petrochemical fuel (e.g. Diesel Number 1) at 50 vol.%; at least one biosynthetic oil (e.g. peanut oil) at up to 90 (preferably 50-90) vol.%; at least one stabilizer mixture (e.g. additive to maintain cetane levels at or above petroleum fuel requirements for Diesel Number 2 fuel) at 0.086-0.017 vol.%.    USE - Used as lubricant for diesel engines and their related working parts (claimed), and used as biocide to inhibit bacterial growth.    ADVANTAGE - The fuel composition meets quality standards ASTM 975M and ASTM 6751, prevents the loss of horsepower and torque of the diesel engine, prevents abnormal wear of engines, reduces sulfur emissions of the diesel engines, and produces a minimum of environmentally unattractive by-products. The composition is equivalent to Diesel Number 2 fuel in terms of lubricity, pour rate, flow rate, power and engine speed, but is cleaner burning and considerably less costly.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for manufacturing a fuel composition for diesel engines comprising:    (A) prefiltering the biosynthetic oil through a 25 microns polyester filter at 105-125degreesF;    (B) analyzing the mixture for moisture, insolubles, and unsaponifiable material (MIU);    (C) requiring that the MIU content to be less than or equal to1.5%;    (D) re-filtering through a 25 microns filter at 105-120degreesF filtering again within the same temperature range through a 10 microns polyester filter;    (E) further filtering the mixture through a 5 micron polyester filter;    (F) settling the mixture for 3 hours in cone tanks;    (G) removing the sediment from the bottom of the cone tanks;    (H) adding 10-50% (v/v) petroleum diesel and blending at 110degreesF;    (I) letting the mixture sit without agitation for 120 minutes;    (J) adding stabilizer mixture (0.086-0.17% v/v) to the mixture and blending at 100degreesF for 60 minutes;    (K) transferring the mixture and spinning for 13 minutes at 2700 rpm using a liquid separating model CINC (Not defined) centrifuge; and    (L) tansferring the completed hybrid fuel to storage tanks.