Nowadays, industries are trying to achieve reduced wastes; reduced Lead Time and improved Productivity to stay competitive in the market by adopting lean manufacturing techniques. For this reason a number of lean tools and techniques are implemented in industries. The goal of this paper is to improve productivity in the production line of truck mounted fuel tankers at Mesfin Industrial Engineering P.L.C Metal Industry using Dynamic Value Stream Mapping and other lean approaches. The methodology of the study is to firstly map the existing stage of manufacturing with the help of current state Value Stream Mapping and to identify the waste areas in the production line, secondly to use lean tools and techniques to effectively support future state Value Stream Mapping for production line improvement. Through this case study, the existing stage of the production line is mapped with the help of Value Stream Mapping process symbols and the biggest improvement areas like excessive Work in Process, lead time, cycle time, are identified. Some modifications in current state Value Stream Mapping are suggested and with these modifications dynamic future state Value Stream Mapping is prepared. Further TAKT time is calculated to set the pace of production processes. Current state and future state of the production line are compared and witnessed: the results show that 47.45 % reduction in lead time, 50.2 % reduction in work in process time, 43.1 % reduction in travelling distance, 59.2 % reduction in total waiting time, 72.72 % reduction in number of work in process products, 89.65 % increase in the yearly throughput of products from 58 products/year to 110 products/year, and over 89.65 % increase in the yearly sales revenue of products from 20,010,000 ETB. to 37,950,000 ETB. The number of workers has been reduced 7 % from 72 to 67. The overall process cycle efficiency has been improved from 19.85 % to 37.78 % and On-time delivery of products has been improved from 52.2 % to 99.0 %. The findings are limited due to the focused nature of the case study. Dynamic Value Stream Mapping can also be applied to the process industry as well as to the service sector. This case study shows that dynamic Value Stream Mapping is a powerful tool for lean implementation and allows every industry to understand and continuously improve its understanding towards lean manufacturing.