Water pump failure is one way to ruin your weekend cruise or track day. Stay on top of your BMW's maintenance by replacing your M50/M52/M54/S50/S52 water pump before it fails and overheats your beloved inline six. The engineers at Mishimoto have developed a high-quality replacement water pump to continue supporting our E36/E46 customers in every aspect of their cooling system needs. Our water pump features a durable cast-aluminium body and a composite impeller for improved durability. Debates over impeller material are not uncommon. Our team determined that our composite impeller provides optimal durability in extreme conditions while being less taxing on internal bearings compared to a metal impeller unit. Along with robust construction, we also include a new water pump O-ring for hassle-free installation. To further protect your cooling system and improve water pump lubrication, refill your system with Mishimoto Liquid Chill® Synthetic Engine Coolant. As with all our products, this water pump is covered by the Mishimoto Lifetime Warranty.