I see I did not keep up with the progress of this thread that I started. I did finish the installation of all 4 shocks in late July.
Yesterday we just returned from a 2 week trip out west to Colorado and Wyoming (from the Chicago area) so I got some serious use from the new heavy duty Bilstein shocks on our 2007 E350 chassis. I have drawn a conclusion.
First I want to say that the shocks the new Bilsteins replaced were 11 year old Koni-RV adjustable shocks. I cannot compare the two brands because the old Koni-RV shocks were not adjusted to the heavy-duty setting as I had been told by the installer. I think the technician simply installed them out of the box without any type of adjusting. Each shock was adjusted differently, favoring a middle setting. What made me replace the shocks was worn-away top-mount grommets on the front shocks.
New shocks are always going to be better than old shocks, especially when the old ones were adjusted wrong and with tired grommets. So I won't compare the two.
What I can say is that surprising to me is that the new heavy duty Bilstein shocks added only a very minor increase in the harshness of the ride compared to the old Koni-RV adjustable shocks. I expected a much bigger change, a significant increase in the harshness of ride. If someone changed my shocks without my knowledge, I would not notice any increase in ride harshness. Given my old Koni's were not adjusted to the heavy duty setting, I can see why the very minor increase in ride harshness.
As hoped, the new HD Bilstein shocks eliminated all of the front end bouncing up/down porpoising I had with the messed up Koni shocks and the Bilsteins noticeably improved handling. My front tires are original 11 years old with 38,000 miles on them with uneven thread wear, much caused by the messed up Koni shocks. I assume our rig will be back to 100% after I replace the tires and get our front alignment checked.
If I had a chance to do it over again, I would still install the same heavy duty Bilstein shock absorbers.
