The "quiet" side of the park is quite a bit different than that "other" side. In the Grand Lake area there are 2 commercial CG/RV Parks -- Winding River Resort, as previously mentioned and Elk Creek CG. Both are very nice, both are between town and the entrance to Rocky. Winding River, to me, seems a bit more spread out and diverse. The full hookup, big MoHo area seems to be more akin to what one expects, a few rows of RVs in a line. The other areas, with W/E and dry camping (yes, they offer dry), are interspersed in a couple different areas. They offer showers/laundry facilities and other activities on site.
There's Timber Creek inside RMNP. It's first come/first served, has paved roads and is a great place to stay for dry camping. Used to be in a stand of trees until the beetle kill came along. Lots of stumps and open areas, not a lot of shade, but then it doesn't get overly hot there either.
Besides Stillwater, there are several USFS CG south of Grand Lake, toward Granby.
H E R E is a link to what you may want, consider the ones listed for Granby. Stillwater does offer W/E hookups, it's about 7 miles to the entrance to Rocky. Arapaho Bay is also nice, it's off the highway about 9 miles back, and more primitive. It could be a bit tight, however, for your rig. Check the other listings for Granby to see what could work for you, if you want to consider this option.
There's also YMCA of the Rockies/Snow Mountain Ranch CG, which is listed under Granby, but is actually between there and Winter Park, closer to Tabernash. It's a wonderful place to stay, they have FHU at their CG. Only problem is it's really hard to navigate their website, as it gives a lot of information on the EAST side in Estes Park. the CG is listed under lodging and you have to use multiple pull downs to get to the info you want. Just another place to consider, though.
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