I'm going to get flamed for this again, but, our Jeeps are rated for 2000lbs towing. I take that as being your average utility type trailer, but with a decent hitch on the Jeep.
I routinely pull our 2500lb travel trailer with my Jeep and to do so I added a hidden hitch (bolts to frame not just the cross member) added an electric brake controller, and run a weight distributing style tow hitch in the receiver. Added to the "hard" parts, you have to throw in some common sense as well, if possible stick to side roads verses freeways (all roads here are side roads), leave plenty of stopping room between you and the car in front of you and don't forget to use extended towing mirrors so you can see behind you. Also, be sure to properly balance your load, no matter what you are using for a tow vehicle. Just for sh!ts and giggles I was looking through our owners manual for our 1998 Ford f150 supercab 4x4 with 5spd and 4.6l, turns out it's only rated for 1700 lbs towing. Yup that's a full 300lbs less than a YJ, and you see them towing all day everyday.
You will be breaking the law, but probably not as bad as the Kid texting behind the wheel or the soccer mom putting on make-up. or the fellow heading home after a few beers from the bar. Pick your poison, we all break laws to some degree.
A 2000# tow rated hitch adds that much to the GVWR.
Um, ..... No, it just means the hitch is rated to 2000lbs, your brakes etc. still remain the same and most definitely will not stop a 4000lb trailer with no trailer brakes, not to mention keeping the front wheels on the ground.