Recent tactical vehicle development has focused on balancing protection and mobility through reinforced hulls, modular armor, and advanced mission systems. These upgrades have inevitably increased the gross vehicle weight (GVW), demanding higher engine performance to maintain mobility. This study analyzes the relationship between GVW, engine power, and power-to-weight ratio (P/W) across various international tactical and MRAP vehicles to assess how technological progress has compensated for weight growth. The GVW– power correlation illustrates generational trends in powertrain scaling, while the GVW–P/W analysis reveals changes in mobility efficiency as protection and payload increased. Results indicate that although engine outputs have risen in proportion to GVW, the overall P/W ratio has gradually declined, implying a design shift toward protection-oriented configurations. From these findings, a reference range of 20–25 hp/t is suggested as an appropriate target for future 4×4 and medium-class tactical vehicles. The results provide a quantitative basis for achieving an optimal balance between protection, payload capacity, and mobility in next-generation military vehicle design.

The mobility of the tactical vehicle is important for a mission completion and survivability. During the field operation of the MLRS(Multiple Launcher Rocket System), broken bolt was found in a final reduction gear with oil leakage. It was confirmed that the final reduction gear pad bolt was broken with ductile fracture after inspecting and scanning electronic microscope of the bolt. Furthermore, a finite element analysis on the bolt was conducted with regards to the operating conditions in the final reduction gear. Conducting the analysis, there was a possibility of the bolt being damaged when we put rusty spline and the adhesion of hub thrust pad as input parameters. Finally, improvements on the spline in the shaft are expected in the future by utilizing the result of this study.