Hi Lend-lease 1.5,
measure from the center bolt in the center of the spring, to each eye bolt, that should tell you what your total length is.
The length should be somewhere from 39 13/16 to 40 inches.
I just had a set made for the front of mine.
My truck is a 45 GMC 400 series 2.5 ton with 9 leaf front springs. they measure 20 inches from center to each eye, total of 40 inches.
If you are going with the original specs you need to know the thickness of each leaf , and the total thickness of the stack.
I have a maintenance manual for my truck that has a page with all the specs for the 300,400,& 450 series trucks.
I gave the spring shop the specs, & they were able to make up a set to the original specs.
There is a possibility I have the same springs as you, depending on the leaf thickness.
This should give you an idea of what to go by.
Last edited by JeffL; 12/03/2013 1:54 AM.