Sometimes a very powerful businessmen may order its suppliers to deliver parts on time (JIT). In this case, if the plant on the retailer to implement Kanban system without changing its own production system. Kanban system will be something that is heavy for its suppliers. Although the kanban system is a very effective way to realize the concept of JIT. This system should not be applied to the supplier without any change in the overall production system user company. Kanban system is only a subsystem of the Toyota production system requires a total reorganization of the existing production system.
If the next process to take spare parts with large variations in the amount or timing, the former was forced to prepare reserves of manpower, facilities and preparations. Likewise, because the parent plant is associated with suppliers through the kanban system, the supplier will have difficulties when ordering spare parts factory in the amount of production fluctuates in line at the end of the raft of the parent plant.
In 1950, Toyota honsha started using a plan balancing line between the end of the raft lines and lines of machining. Then the kanban system was developed and gradually spread further into the process earlier. Consequently, since 1962 the kanban system has been applied to all Toyota plants. Thus, since 1962 Toyota has started implementing the kanban to its suppliers. In 1970, Toyota has implemented a Kanban at 60% of its suppliers. In 1982, Toyota has implemented a Supplier Kanban in 98% of its suppliers, although only 50% of its suppliers that use kanban In-Process (or Supplier Kanban Production) in the factory itself.