I received my D used and one of the previous owners, I know that there have been at least 2, had placed overload springs on the rear.
This spring is not made for this truck for one thing plus he over loaded it at least once and ended up putting a small bow in the front of the main leaf springs on both sides.

So I was looking at replacing the rear shocks and ended up finding some Monroe Sensa-Trac shocks with coil-overs.
But these appear to be for 2wd trucks only.

I checked the numbers between 4x4 and 2wd and the 4x4 shocks are longer.
Has anyone seen something similar for the 4wd models?

I'm just looking for a way to get rid of the overload springs since I'm not happy with them at all.
Without having to get the spring packs rebuilt too.

 

if the stock springs are warped (bowed) they need to be replaced, they have flexed in a way they were not designed to flex and are compromised, its just a matter of time before they break. IMO i wouldnt wait to replace them. (i know this isnt what you want to hear but its how it is unfortunately)

also the sens-a-tracs are monroes low end shock, the reflex line (also by monroe) is the shock you want for a DD