After rebuilding the transmission, brakes and front suspension, I finally got my 65 dart back on the road this weekend. Power steering was working intermittently and fluid was foaming but not making any noises. Was about 15 miles down the road when the steering started to bind up. I pulled over and right as I did, the PS return hose blew (loudly) Both hoses were new. How did so much pressure build up in the return line? What is the issue here?