I have some thoughts.
I found an RV parts and service center who works on anything. I need warranty work on my ONAN, looked on their web site for a repair center and found http://tonysrv.com/
in Lexington, SC. spoke on the phone for a bit to get that feel good vib. They stated that is all they do is RV service work. The work on all brands and employee a person full time that deals with the warranties from RV manufactures to extend warranties and all appliance warranties. No warranty, no problem. First appointment was 3 weeks out. I will drop unit on Saturday, diagnosis on Monday, parts arrive on Tuesday, I pickup on Wednesday. As we leave the following friday, no problem if parts are not there. just reschedule upon our return. We will see.
With mobile service and box store repair centers starting to come of age, I can see an entire repair industry evolving to support the RV and TT owners.
Let us hope that that is the case. And yes I did check with my dealer and was told to take it to an ONAN service center as they do not work on generators. Not what I was told.
We need a sticky for recommended service centers by the forum folks. What a resource that could be.