Hi freeklestweety,
I completely agree with Tom Hanlon. If you buy the shocks yourself from the cheapest supplier you find, and have them installed locally, you will save yourself a pile of money. I also agree you would benefit so much more by replacing all 4 shocks, not just the two rears.
One other suggestion. If you are okay with spending a lot more money, consider the Koni-FSD shocks. They have a patented internal valve not found in any other shock absorber. The benefit is that the shock is soft for minor road flaws, but immediately becomes heavy duty when conditions call for it. The patented valve is simple & reliable, not complex or susceptible to issues. It is inside the shock and works off the severity of sudden axle movement. I understand that it helps a lot to address the jolting from expansion joints in the pavement. I don't have Koni-FSD shocks because back in 2007 when I had our suspension issues addressed, they were not available for the E350/E450, just for larger truck chassis rigs and huge buses. About 3 years ago Koni started producing them for the E-Series chassis. The technology has been around for a long time. It is proven technology. When it is time to replace our Heavy Duty Koni shocks, I am buying the Koni-FSDs which are nearly the same cost as a new set of tires.
