Designers are under increasing pressure to provide powertrain systems which meet tougher market and legislative requirements for:- performance, emissions and economy reliability and durability noise and refinement To meet increasing competition, powertrain products need to be “fast to market and right first time”. This implies the evolution of existing technology, comprising multi cylinder reciprocating engines and gear transmissions, drawing on a database of decades of powerplant design experience.It is with this background that CAE has proven engineering value supporting key areas of powertrain engineering to meet these technological challenges in a cost effective and timely manner.This paper follows the analytical engineering of a four cylinder engine crankshaft from concept to production design. Particular emphasis is placed on the integration of concept design software tools and the combination of finite element analysis and dynamic models with reduced degrees of freedom.The validation of such software tools is fundamental to engine analysis. The instrumentation of a production four cylinder crankshaft for the measurement of internal forces and moments is described. Fired engine test results are compared with those calculated at each stage of the design process.