Mike in Oly, it's not just about the weight of the camper, but how it sits in the bed. I found the AF990 to be a great fit for my extended cab dually. It's "center of gravity" point (COG) is just forward of the rear axle, so 96% of the total weight goes over the rear axle. I previously had a much lighter Lance 11.5 that had it's COG way behind the rear axle, made for some poor drivability as I really had to work to keep the truck from wandering as too much weight was pulled off the front axle. Although a COG location does not seem to be an important issue, it can significantly effect drivability more than the actual weight of the camper. I see that Northwood does not list the COG points?