Originally Posted by das_peikko
The heavy duty springs will shake the fillings right out of your teeth.
That's up to the shocks, not the springs.
The springs will set the ride height and overall "stiffness" - load carrying ability, etc. But the oscillation dampening of the spring - the cycle with which it repeats, and strength of that rebound, is governed by the "shock absorber" - very literal name, they have. If he were to put in super stiff springs and cheap Monroe shocks, then yes, you'd likely be right.
I have only Bilstein, Boge, and KYB shocks in our various vehicles. Quality matters here, and the OP showed some savvy about that in his 1st post by circling in on that. Even with the stiffest springs made for two of those (Bilstein for an Audi and ARB/OME for the SUV), they ride like luxury performance cars, not Conestoga wagons ( I was (re)watching "dances with wolves" earlier tonight with my 10 year old step-daughter, so that image comes to mind).
I think HD moog coils and Bilstein springs sounds like a good plan. I don't own a Durango and know the ins/outs of them, but this is not a bad plan on spec. There must be a Durango forum out there, so you could run the idea by them, too.
So I don't know the exact suspension set-up of a 2011 Durango. Is it struts in the front and solid rear axle w/independent coil/shocks in the rear? Or something more old-school up front? is it truly AWD like you said, or more accurately 4WD/selectable?