I agree you see over loaded RV's of every type. The regs in different parts of the country like us up here in Canada vary. In BC where I live you can't haul a trailer with a wet weight of more than 10,000 lbs with our taking a drivers exsam and test to get the endorsement on your licence.
To take the test you have to have the correct veihicl to pull the rig that weighs over 10,000 lbs. So a guy ( having a friend with the correct licence drive the rig to the test location) showing up at the place to write and take your test with. 1/2 ton truck, cause it's not legal.
Also "if" you happen to be in a acedent with a over loaded RV or for that matter any thing over loaded, your insurance is void.
There are a lot of people up here that still drive over loaded and don't care. What they forget is that by them driving over loaded on on the Hwys they are putting their lives at risk as well as everyone else the meet on the Hwy.
In Alberta the laws are way different from BC, and every year we usually will see someone ( not just albertians) have gone down one of our mountain passes and burned up there breaks where they either crashed, or did manage to stop and the rig catches on fire and burns. Sometimes these RV fires start Forrest fires, which is a whole different three.
I always just say to the wife..... some peoples kids....
And no it not against the law to beef up your suspension to "help" you haul an over weight vehicle, however it is against the law to take that truck and RV onto the public roads.
Soup..