I have had some of the same problems with my 2013 Itasca Sunstar 26HE.
So far, I have had issues with the jacks (pump and return lines were replaced), electric steps (motor replaced), and the slideout (front rails replaced).
I have a good dealership. The return jack lines have been replaced twice. My mechanic was concerned about the OEM lines failing again, so they initially used Eaton lines until they found out the Eaton lines were not rated to hold the pressure for long periods of time. Once the Eaton lines started to bulge, they went to Gates lines which seem to be superior to the OEM and Eaton lines. So far, no more problems with the lines; however, the o-ring at the pump started leaking. As expected, the system looked for the next weakest point, which was the pump o-ring. Once replaced with a heavy duty o-ring, the system has been fine (knock on wood).
The jacks and slideout mechanism are all made by Lippert Components (owned by Drew Industries and renamed LCI Industries in December 2016). Drew Industries bought Actuant Corporation (Kwikee Steps) in June 2014.
I know, probably more than you wanted to know....
No problem with my generator, but the original was stolen when my motorhome was burglarized. The original only had about 80 hours on it and the new generator only has about 40 hours on it.
Hope this helps.