The Effect of Some Friction Reducing Additives on Diesel Engine Performance.

The effect of four “fuel economy” additives on engine performance has been evaluated in both laboratory and field engines. The additives included a colloidal graphite, a colloidal molybdenum disulphide and two oil soluble molybdenum compounds. The purpose of the program was to evaluate the additives with regard to engine wear and deposits and not fuel economy.

Engine performance debits were encountered for all four additives, ranging from engine failures to high piston ring wear and groove fill and oil filter blockage. Similarities between the field and laboratory engines were observed for piston groove deposits and ring wear.