if you crank the torsion bars up too high, you get more bounce and they will break.
Unfortunately the other Van site is dead and that is where i got the part number for the Durango shock replacement. All you have to do once you have the shock is cut off the lower mount. So i bought the 2wd model and cut the lower mount off. looks like the 4wd model has the correct mounting for the Van.
https://www.tirerack.com/suspension/...0&autoModClar=
Double check the spec for suspended weight for this shock before purchasing. It has been over 5 years since i did this mod. I dont even have a van anymore; someone stole it and set it on fire.