Thanks for the info everyone, I really appreciate it! My Dolphin does have it all - sink fridge stove oven heater and toilet - and I realize that makes it a much heavier vehicle, as opposed to my friend's Chinook that doesn't have any of that equipment. I will definitely throw some gear in there and go get it weighed (at the dump!), and thanks for the suggestion to weigh front tires and rear tires seperately, good idea! I will also pull the rear wheels and inspect them and the bearings.
As for the recall information on my vehicle, I tried to look it up on nhtsa.. 1978.. toyota.. they don't list anything about a dolphin motor home either in the make or model (under toyota).. so I assume that means no recalls? Any help there?
Again, thanks so much for your help, everybody!