Extended shackles: pros and cons

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Topic author
Yogi
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Extended shackles: pros and cons

Post by Yogi »

Howdy, amigos. Lately I've observed a number of waggies with what look like rather old lift jobs the utilize what appear to be 4 inch springs and long, sometimes really long, shackles. Anybody know what I'm talking about? So, assuming the castor angle is corrected, what would be bad about a setup like this? Seems like you'd get good flex while achieving something like a six inch lift. Please indulge this nooby...

SJTD
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Re: Extended shackles: pros and cons

Post by SJTD »

Seems like it would wobble around like a fat... um, like a woman of size.

Also, if you add three inches to the shackle you only get about an inch and a half of lift on the vehicle. Could be a little more or less depending on where the axles is on the spring.

Also only works where the frame pivot of the shackle is above the spring so won't work on the rears. Unless maybe the post mount if the shackle is below the frame pivot on those.
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Re: Extended shackles: pros and cons

Post by RamJetFSJ »

I tried them with 4” springs and didn’t like them. They would be fine on a mostly trail rig, but on the street they add to the vague, wandering feeling. I believe the leaf springs exert extra leverage on them due to the extra length. They are able to deflect more side to side.
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Re: Extended shackles: pros and cons

Post by fulsizjeep »

I run 4" springs and 1" shackle on the front and am used to vague wandering.
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tgreese
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Re: Extended shackles: pros and cons

Post by tgreese »

IMO you can get away with maybe an inch or two of extra shackle length, but it's not ideal. Realize that you only get half the lift as the shackle length, so significant lift just from shackle length is out of the question.
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Topic author
Yogi
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Re: Extended shackles: pros and cons

Post by Yogi »

Thank you for the replies, amigos.

Topic author
Yogi
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Re: Extended shackles: pros and cons

Post by Yogi »

How about flex improvement? I mean, front six inch lift springs with extended shackles versus standard shackles. Would the extended shackles change the flex?
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Yeller
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Re: Extended shackles: pros and cons

Post by Yeller »

You potentially can get more travel out of the spring with a longer shackle just by the longer shackle allowing the spring to change length more due to the arch of the spring. The less lift or spring arch you have the lower the benefits become. Part of the issue with higher arched springs is they do tend to be stiffer as the arch increases.
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Topic author
Yogi
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Re: Extended shackles: pros and cons

Post by Yogi »

That's what I was thinking. Thanks.
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