My experience with DW and a long RV. You can fit into most sites, but not all. I have a 40' Fifth wheel and the Full and Preferred areas I only had to request to a new site once because there was no way I was going to be able fit the 36' site with two big trees right at the back of it. The one thing about preferred/full hookup is you may have to park your truck down in overflow. I had to do that pretty much every time in those loops.
Premium sites are no problem ever, they are 60' long or better, I have always been able to keep my truck on site.
That said, if you don't want to pay for a premium site or the new $uper premium sites as we decided to call them. You can fit though some patience might be needed if the site is not deep enough. Just make sure to tell them length and total slide count.