We just bought another Grand Cherokee (our third
), so I went over all the fact and figures just a few days ago.
The one thing that makes a big difference, is that factory-installed towing package.
Go for the Class 4 towing package, which gets you a heavier hitch, load leveling rear suspension, a bigger alternator and transmission cooling, and it pushes the towing capacity (of our 3.6 V6) from 3500 to 6200 pounds.
Our 19XUD weighs a shade over 4000, loaded, so that gives a comfortable margin.
One thing to note... the factory package doesn't include a brake controller, so you'll need to fit your own. It's pre-wired, so that's only a 15 minutes job.