The D rated tires you haveon there should handle ANY load you get. 285s in a D rating should be around 3400-3500 per tire, so on par with an E rated 265-75-16 which probably came with the truck. OR higher than an E rated 235-85-16 which would have been the other tire, and those are only good to 3000 lbs or so. I personally on my last truck, found no difference in D vs E rated tires for the loads I hauled and pulled. As I was typically never loaded such that I neededmore than 60-65 lbs on the rear. I ran 50-55 on the front ALL the time.
I would also say as others have said, your truck needs some front end work! The 200 or so lbs lost off the FA should not make up that much difference in handling. I found with my 3500 SW GM, and my dually, it takes about 350-400 before I notice a BIG difference in handling. You should also be able to tow that trailer with out using a WD system, and everything will pull and go straight. I could pull a 12K trailer with my last truck, do so with my dually with no WD and handling is fine!
You might also look at the alignment of the trailer while looking at the trucks alignment also. Both could be out, which would cause the moving issues more so than the hitch adjustments. My personal philosophy is, get the truck and trailer pulling/going straight, then add the sway/wd bars as a safety measure. Too many rely on bars, as if a bar falls off, as I have had, your rig will not be uncontrollable if you rely on the bars! There is no reason to spend $3G on a hensley. Once you get everything going straight, and if you feel you want a bit more anti sway proection if all hecko happens, then buy a hensley!
Marty
