$10,000 is about right and could have been worse for me. I have a Monaco Executive and the aluminum radiator was leaking badly. Called Monaco, they wanted $9800 for a replacement, not including labor or freight. I looked around and found one, exact replacement delivered for $5100 and it was copper/brass/steel. $5100 still seems outrages for what you get. But, way better than Monaco. Cummins did the labor, about $2700 for labor and misc parts and 12 gal of new fluid. They had to put the coach in the air on jacks to remove the radiator out the bottom. Scary seeing a coach flying in the air like that. So, bottom line was $7800, most expensive bill I have had owning a motor coach since 2006.