ORD Shackle bushings loose?

[Bextreme04]

So... I'm refurbishing my suspension and installing a rear shackle flip, greasable bolts and kevlar bushings, and 60" rear leaf springs from a 97 K2500 Suburban. All of the bushings I ordered fit well, except for the ORD 1 1/2" shackle bushings.

They seem to be the right length and shape, but they are exactly 1.5" diameter. The shackle hole itself appears to be 1.55" and the bushing has quite a bit of wobble. The original shackle from the 1980 also appears to have the same larger hole diameter of ~1.56".

I called ORD and they said they have never heard of this problem and maybe the shackles have wobbled out over time? Didn't seem right to me that BOTH shackles would be larger diameter than the bushings. The shackles had tight rubber bushings that had a bit of cracking, but had to be burnt out to remove so I don't think they would have been "wobbled out".

Has anyone else had this issue? Anyone done the 1 1/2" kevlar shackle bushing and had it fit nice and tight?

 

[Bextreme04]

Here’s some pics of the spring refurbish, because.... pics

Disassembled the pack and hit with a flapper wheel to strip the rust and paint

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Painted the contact surfaces with EZ-slide from tractor supply. It’s a dry lubricant graphite paint.

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Assembled the packs with new Teflon sliders and then painted the entire thing with black rustoleum high performance enamel. I didn’t realize until posting this that I didn’t actually take a pic of the final assembled springs. But here’s a pic during assembly of the packs.

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[Curt]

I used the rear heavy duty shackle and bushing kit.All the bushings fit my springs snug.1 1/2”.It was their shackle.But I already had the springs.

On a previous build,I reused my old rear shackles and just put new bushings and they fit snug as well.

Those boys at ORD know their business,but there was some oddities out there.Maybe there was some kind of HD towing option on yours?Previous owner did some kind of mod?Or maybe they are wallared out like they suggested?My old factory bushings would move in my springs quite a bit,but still was a PITA to get out.

 

[Curt]

Do you have a pic of the shackle?

 

[Bextreme04]

I'll take some pics of both sets and post them up. Mine was a 8600GVW 1980 K25 wit hall the heavy duty options, but it looks like a standard rear shackle. Nothing was wobbly though. I didn't pull out the old bushing from the original shackles yet, but I feel like that's my next step. I measured the outside diameter and the thickness of the metal and I get the same 1.56" inside diameter as the shackles I am trying to use from the 97 Suburban that wobble.

I ended up using the ones from the 97 because they were the little bit longer 4.5" length and they didn't have a metal sleeve that I would have needed to cut out like the originals.

 

[Bextreme04]

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Shackle pics... it’s just a standard shackle. I can take a video of it wobbling around, but it’s pretty substantial. You can feel it shift up and down if you hold the shackle and press up and down on the bushing.

 

[Bextreme04]

Just to close this out... I finally stripped the old bushing and sleeve out of the stock 1980 K25 shackles and the bushings fit snug in those.

The GMT-400 shackles appear to be the same size diameter at a glance, but are actually .05" larger diameter than the squarebody shackles. Which is just enough for them to be loose and not work.

 

[Curt]

Just to close this out... I finally stripped the old bushing and sleeve out of the stock 1980 K25 shackles and the bushings fit snug in those.

The GMT-400 shackles appear to be the same size diameter at a glance, but are actually .05" larger diameter than the squarebody shackles. Which is just enough for them to be loose and not work.

Oh hell,I knew you was using springs from GMT-400,but thought you was using squarebody shackles.Glad you got it going!

 

[Bextreme04]

Oh hell,I knew you was using springs from GMT-400,but thought you was using squarebody shackles.Glad you got it going!

I had both the GMT-400 ones and the squarebody ones there, but the GMT-400 ones didn't have any metal liners, seemed a bit heavier duty, and are 4.5" long instead of 4" long... so I was just going to use them since I assumed they were the same 1.5" bushing diameter. That turned out to be a bad assumption. We'll see how level it sits and whether I need to do something to level the front and rear out.

 

[bucket]

The newer ones probably measure out to an even metric figure. But I don't feel like doing the math right now, so it's just my guess, lol.

 

[Curt]

So the way I understand it,I’d say,a shackle that’s 1” longer only nets 1/2” of lift.Maybe because it’s only on 1 side of the spring?Sounds good anyway.I think the stock shackles are plenty strong,My 3/4 ton stock shackles are the same as a 1 ton.

 

[Bextreme04]

The newer ones probably measure out to an even metric figure. But I don't feel like doing the math right now, so it's just my guess, lol.

Yeah, I think they might be 40mm... that works out to a bit less than 1.57" and would be a tight fit like the 1.5" ones are in the stock bushings.

So the way I understand it,I’d say,a shackle that’s 1” longer only nets 1/2” of lift.Maybe because it’s only on 1 side of the spring?Sounds good anyway.I think the stock shackles are plenty strong,My 3/4 ton stock shackles are the same as a 1 ton.

Yes, because math. The front spring mount is a fixed point and you are basically creating a right triangle from the stock rear mounting point and the new spring mounting point. To find out what the actual lift height is depending on shackle height, you would use trigonometry and similar triangle to see what that base height would be at the center pin location. It will actually be a different amount depending on what size spring as well. 52", 56" and 60"(what I am swapping to) will all have different ratios of actual lift to shackle height change.