Leaf spring lengths

[krafty33]

What was the difference between models with the 52" inch springs and the 56". Was it certain models?

[Irish_Alley]

i think it was due if it was hd or not or maybe how many leafs it had

[Chevalade]

Shackle location, front rotor width, and amount of leaves in pack are the differences. Afaik

[Captkaos]

rear hanger location, amount of leaf (spring capacity) and Load rating.

[Jim Rockford]

Bringing this back to the top, I got a good line on a 3/4 ton rear with springs, . if the length of the springs are wrong I can still bolt the rear to my stock 1/2 tons spring correct?

[Irish_Alley]

so your asking can your 1/2 ton bolt to the 12 bolt yes

[Captkaos]

Yes the rearend will work under the 1/2T.  the only difference is the rear hanger location.  The axle location is the same.  3/4T springs were an option on 1/2T trucks making them Heavy Half/ HD versions.

[Jim Rockford]

Yea thinking of doing a LT1/th400 and 3/4 rear for a decent  tow vehicle. possible to move the front hangers forward  for the longer springs on a short bed? I looked  but I really didn't see any of the extra holes that lined up.

[Captkaos]

You move the rear hangers BACKWARDS to for a SWB 1/2T.  Should have the holes there already.

[Jim Rockford]

Thanks I'll check tomorrow.

[kurtdirt1]

i think it was due if it was hd or not or maybe how many leafs it had

so if a 1/2 ton is a heavy half it'll have 52" leafs? my glovebox says "hd rear" and it's a half ton. or it says "hd leafs" can't remember. My 86 has 52" leafs but i have an 85 with 56" leafs (both 1/2 tons) . they both have 5leafs but the 52" leafs have an overload looking leaf and the 56" just has 5 long looking leafs

[kurtdirt1]

Did a search and came up with this


52" reg half
56" heavy half

that sounds weird imo. wouldn't a shorter leaf have more strength or am I thinking backwards.

my 85 GMC Sierra Classic has 56" leafs
my 85 Chevy Silverado has 52" Leafs


So does that mean that the rearend out of the 85 is HD as well? The 85 has a rear sway bar but my 86 doesn't.

[Torque454]

My 79 1/2 has 7 leaf 56" springs and the 86 3/4 ton frame i bought has 8 leaf 52" springs on it. I don't really see a pattern, its almost like they just said "hey lets put 56s on this truck and 52s on that one!"

The holes are in the frame for both spring mount locations. I'm going to likely use the 8 leaf springs under my 1/2t with the 14 bolt 4.10 FF axle. I am also going to mount the front suspension from the 3/4 ton to my 1/2t.  I dont have the ability to lift the body off my 1/2t frame to place it on the 3/4t frame unfortunately.

[Captkaos]

Heavy duty means suspension only not the rearend.  Longer springs generally have more leafs not sure why yours both have 5, as the HD version should have 7.

[kurtdirt1]

Heavy duty means suspension only not the rearend.  Longer springs generally have more leafs not sure why yours both have 5, as the HD version should have 7.

I'm assuming the PO took a few leafs out. The 85 "hd" is lowered (what some people do awes me, lowering a work truck)