Ionic Liquids (ILs) have been explored as possible additives in engine oil for optimizing the tribological performances of Internal Combustion engines. Several articles published in the recent past have discussed Trihexyltetradecyl phosphonium bis (2, 4, 4-trimethylpentyl) phosphinate as a potential additive due to its high miscibility and low corrosive nature. This study focuses on the tribological behaviour of various concentrations of Trihexyltetradecyl phosphonium bis (2, 4, 4-trimethylpentyl) phosphinate and ZDDP additives and their blends in mineral base oil and engine oil. Wear of cylinder sleeve–pin specimens was analysed using a reciprocating wear test rig. Further, surface morphology was analysed using SEM analysis. Addition of a 3% concentration of IL Trihexyltetradecyl phosphonium bis (2, 4, 4-tri-methylpentyl) phosphinate into engine oil demonstrated significant reduction in friction and wear.