The TerraPower-developed mechanical analysis code OXBOW is used to evaluate the mechanical performance of Traveling Wave Reactor core assemblies. Benchmarking work was performed using OXBOW to compare displacement and contact load results against a variety of mechanical analysis codes from the International Working Group on Fast Reactors (IWGFR) for a set of well-defined assembly conditions. Significant differences in results were found in the benchmark problem modeling a thermally bowing row of assemblies in a limited free bow core restraint configuration. This is due to a bridging effect which occurs due to differences in contact modeling methodology. Additionally, significant displacement differences in results were found in the benchmark problem modeling duct dilation under internal pressure, temperature, and irradiation. These differences are due to the fact that OXBOW dilation models account for both stress relaxation and geometric nonlinearities. Differences in results between OXBOW and the IWGFR benchmark participants are attributed to higher fidelity models generated using OXBOW.