In response to the need for zero emissions in the global truck making industry, major truck manufacturers like Volvo and MAN are reworking combustion engines to run on low-emission hydrogen instead of diesel. This transition aims to provide a quicker and more cost-effective solution compared to electric batteries or hydrogen fuel cells. While concerns about job losses in engine-making plants have emerged, the focus on hydrogen combustion engines offers hope for the industry's revival. Challenges remain, such as emissions that require filtering, adapting tank sizes, and the limited availability of green hydrogen. Despite these obstacles, truck makers are investing in the development of hydrogen combustion engines alongside fuel cell technologies. The transition to hydrogen combustion engines is seen as a vital step towards reducing emissions and achieving sustainability in heavy-duty transportation. By repurposing existing manufacturing lines, truck manufacturers aim to accelerate the adoption of hydrogen-powered vehicles and address the pressing need for sustainable transportation solutions.