Integrating product development and production development is a challenging task in the face of rapidly changing product introductions and sustainable processes. Considerable amounts of research and practical efforts have been devoted to achieve increased integration productivity, yet, many modern companies still struggle with this in their product realisation processes. The two prominent product-realisation approaches of product platforms and concurrent engineering focus on improving new product introduction by increased modularisation and improved overlap of activities across organisational boundaries. However, implementing these approaches increases several entanglements and requires efforts in the short-term to gain the desired effects in the long-term. To contribute to this quest, this paper aims to investigate the system behaviours relevant to support required long-term work in managing the industrial practice of product platforming. By applying systems thinking within the system dynamics methodology, specifically causal loop diagrams (CLDs) in a case study within an industrialised house-building company in the progress of implementing product platforming, the objectives were to better understand why the integration challenges are so persistent and if CLDs are suitable to reveal and visualise the barriers to and enablers of the integration of product and production co-development. Two comprehensive CLD models have been developed based on empirical data and model building to extract the mental models of a product manager and a production performance manager, each offering their unique perspectives on successfully managing product and production co-development. Analysing the CLDs provides management insights into co-development between the conflicting perspectives, indicating the suitability and value of the CLD approach despite its limitations. Using CLDs help both to narrate fragmented stories into their bigger pictures to resolve conflicting objectives between department silos and to pinpoint several development potentials for the company in their transition towards proactiveness.