Anti inversion shackles (1 Viewer)

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is there any reason anti inversion shackles shouldn't be used on the 4" lift I am about to buy and install onto my 40?

I am in the midst of deciding on my lift purchase and am coming across soo many different available options to complete this lift. so the question now is : is there a benefit to these anti inversion shackles or will your "standard" shackle be enough?? same type of questions as for the greasable shackle.....why would anyone choose not to go with those or the anti inversions?

thanks for the input!


i've included 2 randoms photos of what i've considered "anti inversion" and traditional shackles...i know the HFS ones are a lot beefier than standard...but i meant basic design.
anti inversion.jpg
inversion.jpg
 

tucker74

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is there any reason anti inversion shackles shouldn't be used on the 4" lift I am about to buy and install onto my 40?
No.

is there a benefit to these anti inversion shackles or will your "standard" shackle be enough??
Anti-inversion shackles do just what they say, keep your springs from inverting in extreme flex situations. I kept the stock shackles when I originally installed my 4" SUA lift, all I can say is keep a pry bar in your rig if you plan on wheeling ;)

same type of questions as for the greasable shackle.....why would anyone choose not to go with those or the anti inversions?
$$ ;)

Good luck!
Tucker
 
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Some argue greasable pins are weak because you have a grade 5 bolt with a hole drilled in it taking away half of it's mass and leaves the potential of breaking under extreme punishment.
 
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Some argue greasable pins are weak because you have a grade 5 bolt with a hole drilled in it taking away half of it's mass and leaves the potential of breaking under extreme punishment.
kind of assumed that too...spare bolt or two on the trail i guess could be helpful
 

tucker74

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Some argue greasable pins are weak because you have a grade 5 bolt with a hole drilled in it taking away half of it's mass and leaves the potential of breaking under extreme punishment.
To expand on this a bit - this strength becomes infinitely more important on a traditional shackle design where each side moves independently, allowing for lateral flex in the springs. This ability is the main counter argument against the tri-shackles, since they obviously don't allow this movement. The linked shackle like you posted above would be the least attractive option, since they don't allow for lateral flex or solve the inversion issue.

I've never broken a shackle bolt either way however, but have lost several nuts & washers on the trail :frown:

Tucker
 
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Are there non greasable anti inversion shackles that you guys would consider strong enough to run with stock springs and 33x9.5s?
 
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The H shackle design is a kludge and I am always amazed that these continue to sell. (That is not a "standard" shackle BTW) Generally in this H pattern approach the bolt is held tight buy the bushing and the shackle rotates around the bolt. Metal on metal wear is not a good thing. They also limit articulation some due to resisting twist of the spring under extreme deflection.
In an OEM shackle the pin is locked in place and is forced to rotate in the bushing as it is intended to do.

You can fix this particular flaw in this design by welding a tab on the side of the shackle to prevent the bolt head from rotating after it is tightened down.

They still limit spring twist though.

There is no need for any anti-inversion shackle if your springs and shackles are correctly matched in length. OME sells a lot of anti inversion shackles because their springs need to be longer.

When the spring and shackle are matched correctly the shackle cannot invert even at maximum spring droop.
When you throw a steeply arched spring under a rig with OEM length shackles in OEM shackle hangers you usually throw this relationship off.


Mark...
 
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Some argue greasable pins are weak because you have a grade 5 bolt with a hole drilled in it taking away half of it's mass and leaves the potential of breaking under extreme punishment.
Just for the sake of accuracy... The ones I have seen and used do not have a hole nearly that large drilled in them.

However if you are using poly bushings, greasing is more important for easy installation than is is for anything else. I do not bother with greasable shackles because the grease really makes little in any difference in suspension performance.


Mark...
 
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Are there non greasable anti inversion shackles that you guys would consider strong enough to run with stock springs and 33x9.5s?
Stock springs and 33x9.50s under a '60... pretty much any shackle will be strong enough. And again... anti-inversion shackles are completely pointless on stock springs.


Mark...
 
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Mark W said:
Stock springs and 33x9.50s under a '60... pretty much any shackle will be strong enough. And again... anti-inversion shackles are completely pointless on stock springs.

Mark...
Thanks for the info. What is the general consensus on adding longer shackles with stock springs for the sake of gaining clearance? I'm sure the truck will get lift springs down the road over the next 1-2 years.
 
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Longer shackels for nominal lift is pretty standard procedure. If you do use them remember to add the proper shim or "wedge" between the the front springs and axel to retain the correct steering geometry. I have a 2.5" over stock shackel lift with 4 deg. camber shims on the front. I ran 32/11.50/15 tires on 15/8" wheels with no problem for years. I went back to factory steelies and 31/10.50 tires so I have absolutley no rubbing.. anywhere. Hope this helps.
 
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Thanks for the info. What is the general consensus on adding longer shackles with stock springs for the sake of gaining clearance? I'm sure the truck will get lift springs down the road over the next 1-2 years.
As mentioned. slightly longer shackles are a pretty routine approach to gain an inch or two of clearance.. and... as mentioned above, you will want to use caster shims too.


Mark...
 

bsevans

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Not all greasable shackles have a hole drilled thru the center of the pin into the major length of the pin with additional holes drilled at 90 degrees to supply grease to the bushings. If you look at the construction of the 4 plus greasable anti-inversion shackles you will see that the pins are made from grade 8 stock with a very short center drill for the zerk fitting and the 90 degree hole is very close to the zerk fitting. The track for the grease is a shallow groove on the outer surface of the pin. In my opinion they are the strongest greasable shackles you can buy. I'm so tired of hearing horror stories about broken greasable shackles from people that bought poorly designed hardware because they were cheaper and then condemn all greasable shackles because they were unwilling to spend the money and buy the best, strongest and most reliable design. I’ve been running 4 plus greasable anti-inversion shackles for at least ten years and the only thing worn out and replaced are the bushings. Please, someone post a photograph of a 4 plus greasable anti-inversion shackle they have broken.
 
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The H shackle design is a kludge and I am always amazed that these continue to sell. (That is not a "standard" shackle BTW) Generally in this H pattern approach the bolt is held tight buy the bushing and the shackle rotates around the bolt. Metal on metal wear is not a good thing. They also limit articulation some due to resisting twist of the spring under extreme deflection.

In an OEM shackle the pin is locked in place and is forced to rotate in the bushing as it is intended to do.

Mark...
Do the "H" pattern shackles use a different (tighter) bushing than regular shackles?
 

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