A well-known Phan-Thien and Tanner differential viscoelastic constitutive equation has been employed to analyze the nonlinear stability and dynamics of nonisothermal film casting. A finite element method combined with stabilization techniques including discrete elastic viscous stress splitting and the streamline upwind Petrov-Galerkin method was first performed for the numerical calculation of transient film casting. Therefore, the stability analysis of film casting was carried out based on a wider parameter space of processing and the rheological properties of the polymer melt, during which the critical draw ratio for the occurrence of draw resonance (Drc) was taken as an indicator for flow stability. Unlike the results predicted by the upper-convected Maxwell model, the stabilizing region upon an upper critical draw ratio is nonexistent, while more than one peak of Drc was observed with varying aspect ratios, which was dominated by two deformation types named planar and transitional deformations, respectively. Our simulation results show that elongational rheological behavior plays a dominant role in the stability of flow for both extensional-thickening and extensional-thinning fluids, while the effects of processing parameters such as extrusion rate and cooling and rheological parameters such as relaxation time on Drc all can be attributed to elongational viscosity. (C) 2017 The Society of Rheology.