Where is s good place for oil change on a 24 foot rv?

Any petro or ta truck stop should be able to do it.

In that small of an RV, you should be able to complete that minor maintenance yourself at most campgrounds (with the owner’s permission of course). If you are not so inclined, there are many mobile mechanics who will do that for you. I do ALL maintenance on my 42’ diesel pusher at campgrounds, after assuring management I will be very careful to not make a mess, spill oil, or disturb my neighbors. In the last several years, I’ve never been refused the courtesy, even at places that stated “NO vehicle maintenance of any kind” in their brochure. Do not let the shops/dealers/etc rip you off, there are better ways to perform maintenance on these coaches.