I bet the shocks take care of 90% of your sway if not more. With the sudden loss of pressure in the shock your rig moves even harder and then the shock can't keep up once it catches the dampening point again.
Ummm, I wonder if the 12yo 9012's on our 4Runner, or the 7yo ones on the Excursion, are having the same problem. The ones on the X, in particular, have that "road grime" look around the top.
All I can say is, WOW. The new RS999012X shocks are a whole new shock compared to the 9012s. WAY beefier, as well as the 9-way adjustability. They are gas filled too, so they extend all by themselves - be sure to get the upper eye in position, then turn until they unlock, and slip the lower one on as they extend or you will have a bear of a time compressing them to get it on. LOL, the old ones had a little damping left but were NOTHING like the new ones.
I have 9-ways on the front, which were another warranty replacement for the original 5-ways. The new 9-ways are a whole new shock compared even to them, way fatter.
The verdict? I have a set of test bumps between Wadsworth and Kipling on C470. If it's gonna sway, it will do it there. It worked for fixing the trailer sway, that was the acid test.
No more sway.
Now I'm excited for the front shocks to start leaking...
The sway bar is still a great idea for towing though. We will see what I can fab up with my new $30 airbags for load levelling.