I flushed my power steering system and ordered it to replace the pump while my old one was gaining miles. System flushed and pump changed. The new pump leaked through the unit's main seal on day one, allowing air into the system. When the engine is cold and the steering is under load, the pump hums with the incoming air. It's very noisy and also extremely locked and frustrating. I have contacted Cardone support and am still waiting for a reply.