Oil and Transmission Fluid Diesel engine

I see that you have a view? That has the Mercedes Diesel, Not sure of you statement about a quart of oil every 620 miles? I had one, it has a large capacity oil pan, 15 or 16 quarts plus the filter, which is more than I have in my Cummins! New during break in, I would check engine oil at every fill up, because until everything gets seated you may use some oil. You should have a display that will tell you when to change the oil, at about 15K miles! Mercedes recommends synthetic engine oil, check their recommendations for what brand and weight to use. As far as the tranny, I believe it is a sealed unit, no dipstick to check it! Manual has recommendations to change tranny fluid and filters, follow the recommendation. Mercedes kinda thinks you should bring their vehicles to a certified dealer to get service, discourages DIY mechanics!! Now not all Mercedes dealers will work on your view, so I would track down a good dealer in advance so you can be prepared! I would not take it back to the RV dealer for chassis work, let them handle the RV stuff, and get a MB dealer to handle engine tranny stuff! OH PIA, the "start" battery is under the drivers seat, big, and requires getting the water level checked every now and then,(I would check every 60 days). Good luck!