Re: QL firming and steering dampener
Sounds like someone purchased the vehicle without a test drive. It also sounds like someone who's never owned a modern luxury SUV. This isn't a sports car or a sedan for that matter so no matter what you try it isn't going to change the ride significantly. You don't say which wheels you have but if it's the 18's then that's a lot of your problem, I hated that 18's on a test drive. I knew within 2 miles they weren't the tires for me, they change the entire dynamics of the vehicle. Try 20" wheels with Michelin Latitude Tour HP's, you'll like the results. Otherwise, since you have the air suspension my only advice is learn to live with it or sell it.
Personally I've owned a Cayenne, Touareg, Trailblazer SS and various trucks. The Overland is the closest to the Cayenne of the bunch, including the Touareg. I'm perfectly satisfied with the WK2 Overland and that includes a couple thousand highway miles combined with some mountain road running at some decent speeds.
2012 Grand Cherokee SRT8 Black/Black