I wouldn't want to get that close to the max tow rating, and you would probably be pushing close to the max payload as well.
A weight distribution hitch redistributes weight off the back axle of your Jeep towards the front. It allows your tow vehicle to ride level while towing (instead of all the weight on the rear, forcing your Jeep "nose up". This is very important for safety and handling (imagine your front wheels trying to steer when they are not quite as "grounded" as the rear).
Here's a diagram.I've been pulling a 17' TT, max 3700lbs, with my gasser Jeep Liberty. Properly setup, it works fine. Not great, not going to be passing on inclines, but it does just fine and I'm happy with it. The closest limit I'm near is max payload. Jeep has to be nearly empty, besides wife and I, 2 dogs. All gear is in the trailer (not much room anyway with 2 huskys in back).
We get about 10mpg towing, on average, sometimes 11 on flats, as low as about 8 with hills.