All, Well, I've done it now. I brought home a new class A. Mine is on the FORD F53 chassis. The oil fill cap & owners manual state it is to use 5W20 motor oil ? WOW! That sure is thin....
In summary, it looks like the V10 will run well with a variety of oil weights. Some will provide a little more mpg and some will provide a little more engine protections. Take your choice.
Again, the recommended oil in Europe is a heavier weight than in the USA.