FORD GENUIEN QUALITY IDLER PULLEY KX6E-19A216-BA FOR FORD EVEREST U375 An idler pulley is a non-powered pulley that guides, tensions, and supports a drive belt in an engine's accessory drive system. Its primary function is to maintain proper tension on the serpentine belt, ensuring that all accessories, such as the alternator, air conditioning compressor, and power steering pump, operate correctly. Product Information Product Name Idler Pulley Car Fitment FORD EVEREST U375