A lot unfortunately. Sadly even more people overload their trucks. For example, the tow capacity on your 2003 Dodge 3500 varies between 10,450lb and 16,200lb depending on the configuration of the truck (rough numbers based on the trailer life guide. So you could be overloaded before you even fill the tanks on that trailer.How many people are on the roads in BC with heavy 5th wheels who haven't got a clue that they are breaking the law and risk a lack of insurance if they cause an accident?
Salesmen usually don't say a word about weight ratings etc. There are some honest ones out there but most don't want to loose the sale and the reality is, most consumers think their trucks can tow anything you can hook to them.
I posted a link to ICBC's page on restriction 20 and 51 back in post #4.First off, you may not be breaking any laws. If you re-read what was posted earlier you will see that it doesn't matter what it is rated for, it is based off what it actually weighs. In your case, if it is over, there is a restriction 51 specifically for RV's that doesn't include everything that the restriction 20 does (at least that is how I remember the difference).
In the case of an heavy house trailer, you need the restriction 51 once your trailer weighs more that 4600kg. So as Mermaid says, go weigh it to make sure but given the 6108kg GVWR I'm pretty sure your trailer weighs more than that.