78 heavy half ton
 

So I was finally able to track down more info on my c15. The paper work says its a heavy half ton. So I'm wondering if I can use 1/2 and 3/4 ton front and rear suspension shocks, leaf springs, ect. I think it's got 8 leafs in rear really would like to use the 4 or 6 leafs there a little cheaper and if all of it would be a bolt in installation. And now I'm wondering what the other differences would be if any or does it just mean the suspension is different?
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Re: 78 heavy half ton
 

The heavy duty rear leafs were 56" long. Standard leafs are 52". Your rear hangars will be in the wrong location if you try to install regular duty leafs.

Re: 78 heavy half ton
 

So could I move the position of the hangers? and is that a something that could be done with drilling a couple more holes and sliding them in more
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Re: 78 heavy half ton
 

The wholes should already be in the frame. You will have to cut/drill out the factory rivets for the shackle mounts to move them back. Use grade 8 bolts when re-installing the mounts further back.

Re: 78 heavy half ton
 

Essentially the "heavy half" trucks are a 3/4 ton truck with 5 lug wheels.
They have the heavier springs and bigger brakes, just not 8 lug axles/rotors

Re: 78 heavy half ton
 

Thanks, sounds like a fun little project ill definitely start Friday night. I don't tow or haul any big loads so I think the 4 leaf will work great well I hope lol. Would you think it's a good idea to replace the shackles or keep originals and just clean up
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Re: 78 heavy half ton
 

not quite....The frame is still a 1/2t frame. Just went through this.

Re: 78 heavy half ton
 

What are you talking about the 4 leafs are 1/2 ton so I'm putting them on a 1/2 ton frame I don't see the issue with that
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Re: 78 heavy half ton
 

The response was not meant for you,sorry. You have the right plan.

Re: 78 heavy half ton
 

Ok thanks then Friday it is . Sorry for the snap
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Re: 78 heavy half ton
 

Yeah, the large springs suck butt ride wise. I've got them on my 77. I would put 4 leaf packs in but I'm too lazy to mess with the rivets.

Re: 78 heavy half ton
 

i wanted to swap mine for the smaller ones too. It rides much better now after the flip. Since your planning a flip too, just leave them you wont regret it...

Re: 78 heavy half ton
 

Mine actually rides VERY nice.

Re: 78 heavy half ton
 

Yea the ride sucks now hopefully when I put the 4 leaf it will be much smoother ride. As for the front suspension is it basically the same 1/2 and 3/4 ton I heard just the brakes are bigger but everything else is the same
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Re: 78 heavy half ton
 

You can remove leafs from your existing spring packs. No rivet messing required.

K

Re: 78 heavy half ton
 

Exactly what I was thinking. Why mess around with new springs and moving shackles when there is a much easier option that will also soften the ride.

Re: 78 heavy half ton
 

Will removing the s couple leafs lower the truck as well I was going with the 4 leaf because of price. my leafs on there now are shot thinking of replacing them
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Re: 78 heavy half ton
 

should. I still would NOT move the spring hangers no matter what.

Re: 78 heavy half ton
 

Would moving the hangers compromise any integrity or stability in the trucks driving the way it rides. I'm asking because if I move the hangers and put new 4 leaf pack I don't want any damage to my baby lol
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Re: 78 heavy half ton
 

The longer 56" springs,with less leafs will have a softer ride than the std 52" springs. I would just remove every other spring(total of 3 at at first) and see how she rides then.

Re: 78 heavy half ton
 

No - no compromise in moving the hangers.

Just replace the rivets that you cut loose with grade 8 bolts.

K

Re: 78 heavy half ton
 

So when I put the 4 leaf pack on will it lower the truck in back. And if so won't I have to do the front at the same time. Hoping it doesn't lower to much
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Re: 78 heavy half ton
 

The amount of lowering will only be the thickness of the leafs you are removing. If you do every other one as directed you should not see anything significant because the curve in the main leaf has not changed. I would go with removing the leafs and not moving the hangers. Dont forget new bushings in all your holes while you have it apart.

Re: 78 heavy half ton
 

I will add, if you have the extra heavy duty front coil springs (1050 lb/in I believe), its going to feel unbalanced with the now soft springs in the rear and the "firm" springs up front.

Alex.

Re: 78 heavy half ton
 

Sure it will. With less support of the curvature of the leaves below it, the main leaf will flatten out, causing more drop.
It can also increase axle wrap and lowering the load capacity too. You just have to decide which of these factors matters....and how much.

Re: 78 heavy half ton
 

This is somewhat true when you put a substantial load in the truck. Keep in mind you are not removing all the helpers, just two. this gives you almost the same pack set up as a 1/2 ton. The truck's main leaf will not flatten out.
I have done this. I have three sets of heavy half springs. The reduced pack acted like the set on my 78 C10 Stepside. It is true that the front springs will be mismatched.

Re: 78 heavy half ton
 

I need to remove some leafs on my 56" heavy half leafs too

Re: 78 heavy half ton
 

1/2 came w 1,475 or 1,550 coils. HH 1,625 or 1,700 (GM info)

Re: 78 heavy half ton
 

So I know I have the 1.25 front brake rotors which means heavy duty.. Well what calipers do I buy 1/2 ton or 3/4 ton calipers. I heard the 1/2 and 3/4 are the same calipers just different rotor size..

Re: 78 heavy half ton
 

What did u mean by, front springs will be mis matched?

Re: 78 heavy half ton
 

Hey straight six. I talk a lot but dont get a lot done. But today...seriously considering removing leafs from my 78 Heavy half or even flipping. Id love to get rid of the thickest bottom leaf then 2 more, (every other one) before I flip and see if low enough. Hope you keep posting how you;re coming along.

Re: 78 heavy half ton
 

So I guess nothing on my question about what front calipers to use on 1.25 hd front rotors

Re: 78 heavy half ton
 

Here you go: LMC Truck Parts (must have catalog) pg 175, pn 34-3912-Z is caliper set for 73-78 1/2 AND 3/4 ton 2wd. $49.95ea w $30 core chg

Re: 78 heavy half ton
 

Awesome thanks.. And I just bought a new 56" 1950lb 7/1 leafs for rear I don't want to move the hangers.. I'm gonna put the mcgaughys drop coils in front should be fine...

Re: 78 heavy half ton
 

Yeah, moving hangers would be LAST option.. I have 7/1 (7 w THICK bottom helper, right?), but want to remove 3 of them to see if low enough w extended shackle I put on this week. And I saw somewhere, today I think, how much coil to cut on these hd front coils. Did u see it, what did it say?

Re: 78 heavy half ton
 

They also have a heavier rating so you pay more to license them (at least here in Calif). I have a 77 heavy half. The smog devices are the same as 3/4 ton also. For 77 no cat and no EGR.