It's taken me a few years to get this truck to the point where it's fairly fun to drive while towing. I should add to my sig that I use a Hensley Arrow and the truck has also been equipped with Landyot Radius Rods. Depending upon road conditions, i.e size of truck blowing by me, wind, condition of pavement...I still can feel a little squirreliness in the rig. I really wouldn't classify it as "sway". At this point, I've done just about everything to this truck that's imaginable; for towing, but I want it to be just a little bit more perfect. I'm now wondering if my tire selection is the problem. I put BFG AT T/A KO 285 75/16, (E load range) on the stock wheels and then learned than my stock wheels are 7" wide. The recommended minimum wheel width for the BFGs is 7.5". Maybe I'm getting a tad too much sidewall flex and that is what I'm feeling. Unfortunately, if I go back to the stock 265 75/16, the tires will look like little donuts because of the additional lift that the heavier suspension provided. The other strange thing that I recently noticed is the amount of body "roll". To test my sidewall flex theory, I unscientifically pushed against the side of the truck to see if I could actually see sidewall flex. What I actually saw was more body roll than tire sidewall flex. So now I'm even more confused as to a possible next step. Any ideas? Thanks.
I had the same problem with my excursion, but when i put 20's with nitto extremes on it it went away and so did some fuel mileage.
Maybe an adjustable shock like the Rancho 9000 would help. Play around w/the valving settings when towing.