This study examines shape-stabilised phase changing materials (SSPCMs) for enabling temperature-dependent tuning of stiffness and damping. While literature and a reassessment of previous work showed a proof of concept between a decrease in stiffness due to chain mobility and an increase in stiffness due to thermal wax expansion, it did not provide sufficient accuracy. To obtain more reliable insight, in-house SSPCMs were designed, manufactured and characterized using a DMA machine. Small, well-controlled specimens allowed direct measurement of viscoelastic properties revealing clear tunable behaviour linked to the wax transition. The results demonstrate that SSPCM tunability becomes evident only when the wax content exceeds a certain threshold.