The exact limitations for towing in a particular situation depends heavily on the state and is at best ambiguous. It’s why you get the “tow police” in online forums, because where an answer can go either way, some will just jump in to argue for a little excitement in their life. For example, just about any size ‘recreational vehicle’ can be towed under just about any circumstances with absolutely no specialized training.
In any case you shouldn’t exceed the rate weight of your truck.
GCWR = Gross Combined Weight Rating GVWR = Gross Vehicle Weight Rating
The exact GCWR limits of your truck will vary even between trucks of the same make and model due to options, so the only definitive method of determining your weight limits is by reading the sticker in your door jamb. If your GCWR is less than 26,000 you still can’t exceed the rated GCWR of your truck. If your particular setup is legal with your driver’s license in the state your vehicle is registered, you may drive it in other states.
There is a lot of debate online because the laws for towing are inconsistent and full of contradictions, because all these specific laws were put in place by lobbyists for a particular agenda. That’s the only way it makes sense that there is practically no limit for recreational vehicles if you do not exceed the weight ratings for your vehicle.
Even if you do not have a Commercial Driver’s License you still need a DOT registration number if you are carrying loads for hire interstate (between different states) or intrastate in most states. (List of states that require intrastate carriers to get a DOT registration number https://www.fmcsa.dot.gov/registration/do-i-need-usdot-number#states)
Getting a DOT registration number wouldn’t seem to be much of a burden except that you are required to get a huge insurance policy to make it more lucrative for others to sue you. It’s interesting that you need to put a DOT number on the outside of your truck which lets everyone know you’re carrying over $750,000 in liability insurance.
Whether or not you have a Commercial Driver’s License, you still must keep your GCVW within your truck’s limits as posted on the door jamb sticker. If your truck cannot haul significantly more than 26000 pounds GCWR, it would seem illogical to go through the additional requirements of maintaining a Commercial Driver’s License.
Beyond the question of general legality there is also the issue of per axle weight limits regardless of the status of your driver’s license. The only way to make sure you’re in compliance is to weigh your rig at a scale at a truck stop. It’s one of those things that’s a lot easier to deal with before you are being inspected at a weigh station. If you’re only a little over you can do things like remove fuel.
Any “commercial vehicle” over 10,000 pounds, which is the weight of a modern heavy duty truck without a trailer or load, will have to stop at all weigh stations. I would not expect much policing of weight limits outside a weigh station.