Multiple suppliers have developed new cordierite 10.5″ OD substrates in China market. One key issue is to evaluate the feasibility of their applications to diesel SCR markets. To this end, test procedures were conceived and performed towards multiple substrate characteristics. Besides typical parameters such as product dimensions, structures, and material strength, thermo-mechanical properties were characterized by hot vibration, thermal shock and thermal cycle tests. Flow performance before and after tests was characterized by a hot flow bench.Four suppliers were selected to provide product samples which went through these developed rigorous test procedures. Comparisons of multiple properties were made. Conclusions regarding their applicability and recommendations for future work are provided at the end.