This study investigated the adsorption phenomena of modified vegetable oils on steel contacting surfaces. Mineral additives are the major additives applied for the modification of vegetable oils. However, an organic additive that is biodegradable is necessary considering the environmental challenges posed by mineral additives. Hence, the study investigated the adsorption of organically modified avocado seed oil and palm (ElaeisGuineensis L.) oil on steel surfaces. The organic additive used was ginger and mustard seed extracts. The Gibbs adsorption value of -18.41 kJ/mol for avocado oil at 3500 C was greater than that of palm oil (-17.26 kJ/mol) implying that the modified avocado seed oil was superior to that of palm oil at elevated conditions (120 – 300 N). The avocado seed oil performed better than the palm oil when modified and performed less than the palm oil in its unmodified condition; the decrease in the value of COF of avocado seed oil from 0.16 to 0.054 proved its serious lubricating ability over the palm oil which witnessed an increase from 0.113 to 0.114. The Gibbs, friction, wear, and physicochemical properties, all suggested better adsorption phenomena of modified avocado seed oil on the steel surfaces over modified palm oil.