I have an 02 X and am towing similar weight/length. I bought it used at 2 years old with 17k miles. I was ready to trade mine in after a month of owning it, the marshmallow feel wasn't confident inspiring for a HD SUV! I first adjusted the steering box, no help. I then installed my air bags from a previous vehicle, no help, but did fix the sagging rear (of the X)! I then installed the Hellwig rear away bar and it made a HUGE difference in how the X handled. No more rear axle steer from the soccer mom rear springs.
I also have a Reese Dual Cam that is dialed in perfectly, I highly recommend this hitch! It is a step below the Hensley and ProPride.
My setup is rock solid now and nothing upsets it when going down the road. I have done 14 hours in a day and am not "worn out" from towing or stress.
Also make sure the tires in the X are "E" rated and inflated to 75 front and 80 psi rear. Same for the trailer tires, "E" rated name brand tires inflated to 80 psi.
02 Ford Excursion V-10 4.30 gears 5 Star Tuner Y-pipe mod Hellwig sway bar Rear Airbags
Prodigy and Dual Cam
07 Cherokee 32B
Better to have a bad day of camping than a good day at work!