This diesel glow plug relay is designed to match the fit and function of the original relay on specified vehicles, and is engineered for durability and reliable performance. This part is compatible with the following vehicles. Before purchasing, enter your vehicle trim in the garage tool to confirm fitment. [Chevrolet C4500 Kodiak: 2003, 2004] - [Chevrolet C4500 Kodiak: 2003] - [Chevrolet C5500 Kodiak: 2003, 2004] - [Chevrolet C5500 Kodiak: 2003] - [Chevrolet Silverado 2500 HD: 2001, 2002, 2003, 2004] - [Chevrolet Silverado 3500: 2001, 2002, 2003, 2004] - [GMC C4500 Topkick: 2003, 2004] - [GMC C4500 Topkick: 2003] - [GMC C5500 Topkick: 2003, 2004] - [GMC C5500 Topkick: 2003] - [GMC Sierra 2500 HD: 2001, 2002, 2003, 2004] - [GMC Sierra 3500: 2001, 2002, 2003, 2004]