We had a Northstar 850SC on a F250 5.4L gas. I would not recommend putting it on a 1/2 ton pickup. When fully loaded we were pushing the payload capacity of the 3/4 ton, and wished we had it on a F350 (which we have now with a larger Northstar camper). We got between 9mpg and 12mpg, depending on terrain and wind. Hope that helps.
2014 Northstar Arrow U
2012 Ford F-350 4x4, CC, SRW