The main purpose of the engine lubrication system is to supply lubricating oil to all moving parts in the engines to reduce friction rates. The failure of this can cause damage to the engine system. The aim for this project is to develop a user-friendly device to predict as accurately as possible the next oil change for an automobile. The device consisted of four main parts, the electronic part, the heating element, the main body and the cover. A 12V DC motor is used to measure the current as the shaft connected to the motor immersed in fluid which temperature is controlled at 40 Celsius. The experiment was conducted using waste oil lubricant (WLO) collected from an automobile servicing centre. The behaviour of a given fluid was analysed using data generated. A measure of viscosity was calculated. The upper limit of viscosity change is set to +15% change and -10% for lower limit. The result shows the deterioration of WLO in term of viscosity. From the sample tested with the device, all the WLO were overused as the oil was over the allowable limit of viscosity changes which could present a danger of possible damage to the engine. Therefore, this device can function as a preventive maintenance device of car as the user can predict when is the best time to change their automobile oil lubricant.