Sprinter 3500, long wheelbase and lengthened body. Gross weight 10k, on a 9.3k scale. I'm not overweight, but I'm heavy! The rams in the driveway and the bog on the dirt road created a lot of top-end spin, and those SuperSprings (plus matching front ones) quelled more than half of the wobble. Love it! Very easy to install, no tools required. Just use a factory jack (good luck finding where it goes) and strong jacks. Pull out old bumper stops by hand, insert new ones with a small stick and some…