The Dana Spicer Air Chamber, part number 977284, is a direct-fit air chamber designed for on-highway axle applications. This chamber is the type of component that controls brake actuation at the axle end, converting air pressure into mechanical force to engage the brakes. Sourcing a genuine Dana Spicer part ensures it meets the original manufacturer’s design intent for your axle assembly. Pro Gear and Transmission carries genuine Dana Spicer parts for the heavy-duty truck market. Call us to confirm proper fit for your specific axle configuration before ordering.FeaturesGenuine Dana Spicer air chamberDesigned for on-highway axle applicationsConverts air pressure to mechanical braking force at the axleDirect-fit replacement for Dana Spicer axle assembliesSold by Pro Gear and Transmission