Several years ago I had a brand new MH with a 4500 genset in it (30a). A loud noise and it stopped working. Took it in to Cummins and it ended up that the turbine shaft broke in the motor and destroyed the inside. Guy told me it happens sometimes, "it either happens within 20 hours or not at all". Replaced it within a day and was on my way. The replacement genset ended up failing as well a few mos later. Running it in the drive before a trip, smelled smoke and it stopped. That time the board fried. Still under warranty they replaced it with a new board. Never had another issue for the remaining 4 years we owned the MH.
You should still check the oil. They will also shut down due to overheat. Happened a few times in the summer sitting in traffic when temps got above 90. Was there a code when it shut off? - the power light on the remote start will blink at a certain sequence to tell you what the issue is.
cummins manualsection 5 tells you the codes.