This article describes the application of multiphysics simulation in the automotive industry. Multiphysics simulation uses a single computational framework for modeling multiple interacting physical phenomena. Within the multiphysics framework, the finite element treatment of fluid flow is based on the Galerkin-Least-Squares (GLS) method, while the arbitrary-Lagrangian-Eulerian (ALE) method is utilized to account for deformable fluid domains. The finite element treatment of solids and structures is based on the Hu-Washizu variational principle. Interaction constraints are enforced in a fully-coupled manner using the augmented-Lagrangian method. Automatically generated tetrahedral grids are used to ease and expedite the analysis process. This multiphysics architecture lends itself naturally to high-performance parallel computing. Several applications are presented which demonstrate the utility and accuracy of this approach in automotive component design. Applications include flows within deformable valves and gas tanks, thermal management of underhood components, and flow within engine cylinders. The Spectrum™ solver is used for these simulations.