A friend of mine just replaced his hydro unit after noticing that the old unit was blowing fluid out of the bottom. At the time that he changed the hydroboost he also changed his powersteering fluid to synthetic. After installing the new hydroboost unit he is experiencing a new problem. It works fine until he turns his wheel left or right. When turning the wheel his brakes seem to be grabbing. Is it a air lock that he is experiencing? Any ideas?