This paper presents structural analyses performed on an in-line, six cylinder diesel engine for noise reduction purposes. Both finite element modeling and experimental structural analysis using digital techniques were performed on the existing design. By applying both of these methods to the same structure, the accuracy of the structural model can be established. After several iterations the results of each method were made to agree quite closely. The finite element model could then be used for predicting the effect of design changes on the structural response of the block.