dayton parts coil springs don't seem to fit

varicella · July 15, 2014

I'm new to this forum and apologize if this post is in the wrong place. I have a 1996 g3500 vandura box truck (14' box) that I am using as a toy hauler / RV. The suspension is completely shot all around and I am in the process of replacing everything. I purchased some new Dayton Parts 350-1205SD coil springs which are supposed to be the most heavy duty ones they have. The problem is they are quite a bit bigger than stock.

Stock springs:

metal diameter: 0.8"

spring bottom outer diameter: 5 3/8"

top outer diameter: 3 3/4 x 4 1/4 (the spring tightens up at the top into an oval shape)

top inner diameter: 2 1/8 x 2 1/2

Dayton parts spring:

metal diameter: 1.0"

spring top and bottom outer diameter: 6"

top and bottom inner diameter: 4"

There are 2 problems I'm having, the first is that since the OD on the bottom is 5/8" bigger, the spring does not fit into the bucket created for it in the lower control arm. Am I supposed to try and remove a little metal / pound this thing in there? It seems *close* to fitting but not without persuasion.

The second problem is at the top, the aftermarket springs (both dayton parts and tuff trucks) do not get tighter at the top, they have constant inner and outer diameter all the way. My truck has an outcropping of metal that sits nicely inside the reduced size top coil and holds it in place. The aftermarket springs would not touch that and could move around, is that not an issue? This spring I ordered is *supposed* to work with my truck so I'm having trouble figuring out if it's really going to work or if I need something else.