This paper presents a case study for an assembly job shop encountered in a hydraulic components manufacturing industry. A simulation model is developed from the data collected and checked the performance of the existing dispatching rule used. Five performance measures are considered for analysis. The performance of each dispatching rule for each performance measure is calculated individually. An Order Review Release (ORR) policy namely Backward Scheduling with Interval Release policy is used for the experimentation. The analysis of results reveals that integrating dispatching rules with ORR policy provides better system performance than using dispatching rules alone. The present study confirms that other dispatching rules other than the existing rule gives better performance.