The purpose of the presented work is to recognize wear in different parts of the gear pump and to determine the wear particle contamination and particle types in oil. Oil samples were collected intermittently from the gear pump test rig to find the wear severity index and particle contamination. The percentage of large particles increased to 80.49% with wear severity index at the end of the test due to contamination. Hence ferrogram slides were prepared and observed under a bichromatic microscope to identify the types of wear particles. These ferrogram slides of oil samples show normal rubbing, severe sliding and cutting wear particles with some red oxide due to moisture content in the oil. Later on, to find the extent of damage to the gear pump parts, surface roughness and changed dimensions of these parts were measured by surface roughness measuring instrument and CMM. The model prepared based on these, gives the simulated results of wear varying from 27.3 µm to 87.8 µm shows a good correlation with actual measurement. In the last part of the work, the gear pump was removed from the system and worn-out parts were cut to prepare samples of the required sizes to observe under SEM. Morphology and texture results given by SEM help to study and predict the wear behaviour of system at particular operating conditions for condition monitoring. The combined approach of experimentation conducted here for quite a longer duration for such type of setup is the novelty of this work.