Is this right? 56" spring question.

[85 Jimmy]

I want to replace my rear 52" 2" lift springs in my truck with 56" springs. Right now I have 6" lift springs in the front, 2" lift springs and a shackle flip in the rear. My goal is to flip the 56" spring and run a zero rate to move the axle back 1.5"-2". That will give me about 5" of lift in the rear, right? So to get the extra inch, I need to replace the 4" shackles, at least I think I have 4" shackles, with cross tied 6" shackles, right?

If all that sounds about right, what do I need to look under for 56" springs? 1 tons, suburbans, newer like 87 and up trucks?

 

[Hogback Fabrication]

Using 56's backwards will move the axle back 4", the zero rate can only move it back forward 1-1/2". So it'll push the axle back at least 2-1/2".

Most 56's came in 3/4 and 1 tons, though they were occasionally used in 1/2T Suburbans. They're usually very stiff out of the box, so people pull leaves to make them softer. If you use them hard like that, they die fast.

 

[sweetk30]

gm spring code for 56" eye to eye springs . in the aftermarket world of part #'s

the 22-547 is 2600 lbs per pack .

the 22-547HD is 3500 lbs per pack .

the 22-617 is 4000 lbs per pack .

the 22-617HD is 4650 lbs per pack .

so watch what ya get . you get your hands on the big stuff even removing leafs wont help much .