This research utilized speed losses to increase overall equipment effectiveness (OEE) at a die-casting company, PT XYZ. Decreased production means that demand cannot be satisfied. This happens because the production machine cannot produce according to the given demand, one of the factors is speed losses production. To overcome this, the define-measure-analyze-improve-control (DMAIC) and total productive maintenance (TPM) used to increase OEE and reduce speed losses. This research aims to improve machine performance, production efficiency, and operations. This research uses the DMAIC method to identify critical problems and resolve problems that affect the efficiency of production machines on the D05E line. TPM used to solving problems found and 5W1H analysis used to analyze problems and develop solutions regularly in various fields. The causes of speed loss consist of two parts: 1. Idling and minor stoppage (41%), 2. Reduced speed losses (8%). The causes of the most significant loss of speed include human factors, machines, materials, and methods. Speed losses as the main issue significantly impact machine productivity, leading to the recommendation of predictive maintenance strategies to replace the current preventive maintenance approach. Implementing autonomous maintenance by investing in machine inspection tools will help enhance the company's productivity.