The report of investigation of the wear behaviour of aluminium alloy samples used in the floating calliper of master cylinder clutch or brake is presented in this paper. As-received commercial aluminium alloy sample sourced from automobile hydraulic brake cylinder calliper was melted in electric furnace under a controlled atmosphere, and sand cast at pouring temperature range of 700-800 oC into rod of 300 mm long by 30 mm diameter. A wear jig was used to determine the wear resistance of the aluminium samples with and without the use of hydraulic fluid. The microstructures and surface of the as-received and cast specimen were examined under high resolution microscope to assess the effects of wear with and without hydraulic oil. It was observed that the aluminium sample wears faster in the absent of hydraulic fluid and was reduced to a bearable minimum when hydraulic fluid was applied. The results obtained are presented in figures showing the wear rates and weight loss of the aluminium samples with respect to the wear cycle, from which models equations are derived. The test results show that eutectic structured cast aluminium alloy behaves relatively better than the as-received aluminium alloy specimen in oil. It is significant that the oil functions as lubricant on the alloy under test, hence the common deteriorations experience from the cast alloy under service must have aggravated from the chemical adulterations in the oil wherewith a thin film of more wear and chemical resistance would bring effective and significant wear and corrosion protection or both to the surface.