There is a small (10 sites) RV campground in Kelowna called Orchard Valley RV Park and it is the absolute best one we have ever stayed in. We have a 38 foot Big Sky 5th wheel that we tow with our Ford F350 and while Orchard Valley does not have any pull-thru sites it has not only enough room in each site for a 5th wheel and also for a truck or toad in the same site. There is shore power in both 30 and 50 amp along with on-site water and sewage. Each very quiet site is separated by 6 foot high cedar hedges which assures each occupant lots of privacy. They also have full showers and laundry facilities within the park. The park is less than 5 minutes from the center of Kelowna and is easily accessible. The reason there are only ten sites is that this is a working orchard (the park is nestled between a pear tree orchard and an apple tree orchard) and the local government allowed orchardists to put in up to a maximum of ten sites to help offset the ever increasing costs of running a fruit growing operation.
The owners, Jim and Seema Khurana, couldn't be nicer and will bend over backwards (so to speak) so that you enjoy your stay.
You can contact them by email at: firstname.lastname@example.org
or by phone at 250-762-9355. The park is located at 2389 Rojem Road and as you come up the drive way make sure to bear to your left as there is another park up the right lane which I have found to not be as good.