Crossland Tankers is a leading manufacturer of bulk-load road tankers in Northern Ireland. These tankers transport up to forty thousand litres of liquid over long distances across diverse road conditions. Liquid sloshing within the tank has a significant impact on driveability and the tanker's lifespan. This project develops a comprehensive LS-DYNA model to enhance the tanker design process and address these challenges. Due to environmental, financial, and time constraints, multiphysics simulations are becoming more prominent in the competitive manufacturing industry. This project aims to develop a general-purpose model of a road tanker that integrates road, tyre, and suspension dynamics alongside fluid-structure interactions, enabling a detailed analysis of various driving conditions. The approach uses OASYS PRIMER as a preprocessor for LS-DYNA, integrating Smooth Particle Hydrodynamics (SPH) to model fluid dynamics and Explicit Dynamic Finite Element (FE) techniques to model the chassis. The model simulates scenarios such as emergency braking to identify areas of high fatigue due to liquid load and sloshing. The validation was conducted through road testing with acceleration and strain data collected using a portable Data Acquisition device (DAQ). By integrating advanced material characterisation for 304 stainless steels with a robust Multiphysics model, this research provides a holistic approach for optimising tanker design for enhanced safety and performance.