The generator from my 05 Excel is currently being tested at the Commins/Onan facility in Orlando. They checked a few things before I left it there and the service manager told me that they had found ...
I have a RT 190P, and the Onan uses a quart of oil. I don't understand disconnecting anything to operate while your driving, I use ours frequently while driving, and in almost nine years have never experienced a problem. I have never used Onan ServiceCenters, but spoke with a fellow B'er, and he said his unit was just three years old and they told him he needed to replace it. He opted for a second opinion - he is running fine! Safe travels.