In response to some of my previous posts under username WILDPEAK (I have changed my username to TireNerd as a result of a job change from Falken Tires to Les Schwab Tires), I am glad to report that I have solved all of the oscillation and highway instability on my 2017 Power Wagon. I purchased airbags and an entire Thuren suspension and installed each item step by step over a few weeks to see which components actually solved the highway wobble, and documented the results with each change.
Initially the OE Power Wagon Suspension had the issue, followed by the Carli suspension with Fox 2.0's (and I was too heavy). With many trips planned on the books and safety being priority, I hastily removed the Carli suspension and installed the AEV suspension thinking that would solve all issues, when I should have just upgraded the shocks to 2.5's or 3.0s.
While not 100% conclusive, ultimately the Thuren-tuned King 2.5 rear shocks with extra rebound damping in the rears combined with the rear trackbar solved the stability issue, the rear is always under control now. Even with the rear sway bar REMOVED, it sways a bit around corners but very predictably and does not oscillate side to side on the highway as it did in the past with lesser shocks. While the main culprit of this issue is the inboard mounted rear coil springs as we all know, the fix is really controlling those inboard springs in my experience. I came to this conclusion when the AEV Bilstein 5100 shocks were blown out after less than 10k miles, and even with the super stiff OE RAM 2500 non power wagon springs, I was able to get the truck to oscillate on the highway, although not as scary as the stock power wagon configuration. At that point, I realized that that no matter how stiff the springs on these trucks, you have to control the side to side motion, either with (1) air bags to move some of the spring rate outboard, (2) more damping control in the shocks, (3) more air pressure in the tires since they are mostly undamped, or as some have reported having success with, (4) a stiffer swaybar (or some combination of those aforementioned solutions).
Because I wanted the best of both worlds, maximum articulation off-road and high speed highway stability for long trips, I opted for NOT attempting to control the rear with the swaybar, that would limit articulation, but rather control it with damping (King 2.5s) and air bags (outboard stability if needed). I suppose if you are super heavy with a camper, maybe you would want to keep the swaybar and/or upgrade to the Hellwig, but that was not needed in my case.
In red are the configurations with issues, the common issue being under-damped rear shocks.
I hope my pain and documented experience will help some others out there for years to come!
www.aev-conversions.com
