OP, You absolutely have no problem with the XJ on your trailer. There are a lot of off roaders in South Florida, Just go out to an off road event and look around. You won't find anyone with a class 3/4 hitch with those stupid weight distribution bars on their trailer. You'll see. Ask some of the older guys who actually trail their rigs to the events. What you are hearing above is what comes from too many warning labels written by lawyers. In 40 years of trailering everything under God's green earth I have never one time seen a hitch failure. I have never had one of my rigs "dive" or "swerve" from a loaded trailer. I regularly towed a trailer and rig two times the weight of your set up with a class 3/4 hitch. The whole thing is set up for 10,000 pounds and you could exceed that without a bit of problem. Your rig and trailer weigh 6000 tops. Those bars do nothing to increase the strength of any part in you hitch or the trailer tongue. they only serve to reduce tongue weight which you can easily do by balancing your rig.
Just ask some of your local guys who know what they are doing and you will toss that crap in the scrap pile.
That's funny because there is no such thing as a "class 3/4" hitch - hitches are rated as class I, II, III, IV, and V, although class V has not yet been adopted by SAE. It's doubtful that wilson1010 even knows what he has.
muddmonkey - you have a 3/4 ton truck (aka 2500), and a class IV hitch. And from the info you've provided, it is not rated to carry 6000 lbs without WD.
Those bars do nothing to increase the strength of any part in you hitch or the trailer tongue.
That's actually the first acurate thing that wilson1010 has said, although he misunderstands why... WD bars are not designed to strengthen the hitch or tongue; they're designed to keep the forces that the trailer is placing on the receiver & truck working in the direction that the hitch receiver is strongest, and distribute them more evenly over the whole truck, rather than just at the rear. This improves steering & breaking stability by keeping the front suspension of the tow-vehicle properly loaded, and prevents the hitch receiver from be subjected to forces in abnormal directions which could cause it to become overloaded and fail in emergency situations.
Think of it this way: if you have to swerve to avoid an accident, the forces that are applied to your hitch receiver change very rapidly. At the moment before you swerve you may only have 500 lbs of tongue weight, or downward force on your hitch receiver. But as you swerve and apply the breaks heavily you could suddenly have 3-4 times those forces being applied both downward and laterally. And those forces change each time you change direction during an emergency maneuver. WD bars are designed to distribute those forces more evenly, and keep them from exceeding the tolerances that your receiver was engineered to handle. These ratings are based on the SAE J684, which is a federally mandated certification that all hitches must have, and the testing for J684 includes testing for WD devices.
And that is why the rating is higher with WD bars than without - it's not because of what the hitch is capable of handling while travling down the road under normal conditions when everything is just right - it's because of what the hitch is cable of handling during emergency situations when the hardware is pushed to it's limits. And the added benefit of WD bars is that it makes the whole rig more stable for normal driving situations.
Either way, your approach should still be the same - get the trailer & Jeep weighed so you know what you're dealing with, rather than guessing. If you then find yourself over the ratings without WD, you should either invest in a WD hitch, or invest a receiver with higher ratings.
Now I'm sure wilson1010 is going to come back with another reply about some statement I've made here, but if you look closely you'll see that he's got nothing to back it up - no facts, no explanation, nothing more than what he's seen, either out on the highway or at the off-road parks. To quote: he's never seen a hitch failure; he's never had a rig "dive or swerve", doesn't "see any problems", and hasn't seen one in use in the last 5 years. So he believes that if he's never seen any of these issues then they must not exist and you don't need to worry about them.
Here - I'll show you a few pictures of class IV hitch failures, just like mine that failed. These are pictures of two different hitches that failed, from a thread on RV.net where the group was discussing these types of failures. Wait - do they really exist?
Both were GM OEM hitches from the GMT 800 chassis, with the 5,000 lb weight carrying / 12,000 lb WD rating:
It's also interesting to note that these SAE standards were created to level the playing field between different manufacturers, by forcing them to test to the same specifications.