Yukon gov't campgrounds are a favourite for us. Only $12 per night gets a nice usually private campspot with fire ring and picnic table, AND free firewood for the fire ring. The outhouses are usually exceptionally clean and well-stocked.
Hardly makes staying roadside worthwhile, where you'll have transport trucks going by most of the night along the Alaska Highway. Fuel and goods are moved to Alaska by semi-truck and the highway is busy through the winter and summer with'em.
Numerous gas stations have dump stations. Potable water is also accessible. When we were tourists in Yukon, we rarely stayed in RV parks, usually just when we needed to wash clothes, humans, and truck, AND stock up on groceries. Once every couple of weeks was enough.
Environment Yukon has a good website for campers/RVers
http://www.env.gov.yk.ca/camping-parks/campgrounds.phpThe map of gov't campground sites is especially useful.
