I have a 2015 AF990 & previously had a Lance 920. I don't see any difference in milage on my 2004 Dodge diesel. I average about 13 mpg. I am not real familiar with Forest Service roads but I have had mine on plenty of gravel roads. As long as you have the clearance on all sides & overhead & the terrain isn't too steep & the road isn't too rough, I would think you would be ok. Last Febr I was in AZ in Organ Pipe National Park. I tried to drive one of the loops with the camper on but the road was just too rough. The bouncing was just too much for me & I figured I would have to go so slow that I couldn't complete the drive in a reasonable amount of time & I would subject the truck, camper & my wife and self to a lot of bouncing and jarring.
Big Rig (John)
