Overview of Mercedes-Benz W203 & W204 Upper Control Arms The Mercedes-Benz W203 (C-Class 2000–2007) and W204 (C-Class 2007–2014) models are known for their refined ride quality, responsive handling, and solid engineering. A critical component contributing to this performance is the upper control arm, which plays a key role in the front suspension system. These control arms help maintain wheel alignment, …