Under an industrial-academic partnership project, the present work aims to map and catalog the different applications of Augmented and Virtual Reality in predictive maintenance (PdM) practices. Through a preliminary scoping review, we targeted two main digital libraries in computing and engineering. Thus, we address the key attributes regarding the types of immersive technologies and the solutions used in several industries for PdM. By categorizing the surveyed prototypes according to 10 parameters in their interaction, visualization, and research methods, we expose the state-of-the-art and valuable knowledge gaps within immersive PdM. After this analysis, we conducted a workshop with 3 manufacturing experts discussing the future of maintenance interfaces, bringing forth their feedback in the shape of recommendations for what to further explore within immersive PdM.