Will 55 Gal drums hold the weight?

Lance, if you have reason to believe that a camper manufacture knows about this, states clearly in their owner guide not to use any form of support with their campers other than the attached jacks. Regardless of their reasons for stating this I can see no reason to ignore their recommendation. Last thing I would want is a 3,000 lb. camper falling off some stands and damaging me or the camper or anything else.

As the saying goes if it ain't broke don't fix it. If your camper's jacks are not broken then use them. If they are not then fix the jack(s) and do it while the camper is in the bed of the truck.