Shackle Question??

I have heard people say the lift shackles are a bad idea because they ruin your stock leaf packs.

When I ask people about budget boosts, they say to get the lift shackles over the AAL because the shackles can be used on a future lift.

So, why is it fine to use shackles on aftermarket leaf packs?

x550x said:

I have heard people say the lift shackles are a bad idea because they ruin your stock leaf packs.

When I ask people about budget boosts, they say to get the lift shackles over the AAL because the shackles can be used on a future lift.

So, why is it fine to use shackles on aftermarket leaf packs?

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It's because the guys who say to not use longer shackles don't know what they're talking about. You can use shackles that are too long, but that is very uncommon on XJ's, and the shackles would have to be very long and homemade.

Goatman said:

It's because the guys who say to not use longer shackles don't know what they're talking about. You can use shackles that are too long, but that is very uncommon on XJ's, and the shackles would have to be very long and homemade.

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why are they uncommon? I've seen lift shackles for XJs or so I thought. How long is too long for a shackle?

Most I have seen are for a 2" budget boost.

I run Rustys 6.5,and have the 1.5 shackles and am very happy with on and off road performance (It drove worse without them).

I can see if you were loaded down with the stock leafs could be pushed flat
with longer shackles (sp?)...but that is a guess.

My wife drives an 01. We recently needed tires so I thought I'd raise it a bit to fit bigger ones. I don't like AAL's. They make the ride more harsh, which for her, was not what we wanted b/c she travels a lot for work. I also don't like the idea of asking that one helper leaf to do the lions share of the work. I've heard that if the leaves are in decent shape, it's not that big a deal. If they are worn out, then there's no way that one leaf is going to hold the pack and it will eventually sag as well. Installing shackles is cake and the ones we got look good.

I've been thinking of doing the same thing except i have a 3in add-a-leaf on my 99xj. Whats it going to be lick with an add-a-leaf? Better, Worse?

x550x said:

I have heard people say the lift shackles are a bad idea because they ruin your stock leaf packs.

When I ask people about budget boosts, they say to get the lift shackles over the AAL because the shackles can be used on a future lift.

So, why is it fine to use shackles on aftermarket leaf packs?

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Aftermarket lifted packs have a larger arch and take more to flatten them out. Stock packs are the worst to use longer shackles on. If you look at your stock leaf spring and shackle setup, you will probably notice the stock pack is nearly if not already flat. Look at the shackle in relation to this. As the leaf pack flattens out, the shackle pushes back toward the rear bumper. Longer shackle means longer arch, means easier for leaf pack to stretch out and flatten or even invert. Did that make sense?

When talking a budget boost or building up lift off of stock leaf springs, blocks are the worst thing you can do, due the the taller fulcrum they become thus causing severe axle wrap. Shackles are not as bad as shackles, but they still cause premature sag for the reason I mentioned above. AAL's come in short and long. Short just suck...period. Longer AAL's help build a stronger pack but are often made to lift a tiring leaf pack on their own so they have a high spring rate causing a stiff and uncomfortable ride. So, it seems you can't win for losing when it comes to a budget boost. If only someone had done their homework and made a kit that used AAL's that matched the spring rate of the stock packs and used several of these AAL's to build up the stock spring pack the way they should have come from the factory. :wink wink:

I have an NP242/Dana35 with around 3.5" of lift. If I were to get a ~1" shackle, how much would I have to shim my axle? The pinion is kinda skyward as it is, however I don't have any vibes. Would 6* be too much? I'm going to SYE this summer when I upgrade to an 8.8 or a 29 spl 8.25 rear.

I have pics of my angles if you need to see.

Edit: Meant this to be in the "Shackles and Driveshaft angle" Thread, but that's ok.

Thats a 1 3/4 or 2" shackle that was part of my Daystar BB. Hasn't messed up my stock leafs, and I chose it becasue like you said, I can re-use it when I get a bigger lift. A+ for the Daystar kit at $97

i used 2 inch drop shackles from a 88-98 chevy truck on my xj for the rear and got 2.25 spacers for the fron off of ebay. in total it cost me about 67 bucks shipped.

Lift shackles are good ! The stock ones will bind when one side is drooped out. I made a homemade lift pack for my XJ and at the same time added lift shackles.

GottaBeJeep said:

Aftermarket lifted packs have a larger arch and take more to flatten them out. Stock packs are the worst to use longer shackles on. If you look at your stock leaf spring and shackle setup, you will probably notice the stock pack is nearly if not already flat. Look at the shackle in relation to this. As the leaf pack flattens out, the shackle pushes back toward the rear bumper. Longer shackle means longer arch, means easier for leaf pack to stretch out and flatten or even invert. Did that make sense?

When talking a budget boost or building up lift off of stock leaf springs, blocks are the worst thing you can do, due the the taller fulcrum they become thus causing severe axle wrap. Shackles are not as bad as shackles, but they still cause premature sag for the reason I mentioned above. AAL's come in short and long. Short just suck...period. Longer AAL's help build a stronger pack but are often made to lift a tiring leaf pack on their own so they have a high spring rate causing a stiff and uncomfortable ride. So, it seems you can't win for losing when it comes to a budget boost. If only someone had done their homework and made a kit that used AAL's that matched the spring rate of the stock packs and used several of these AAL's to build up the stock spring pack the way they should have come from the factory. :wink wink:

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Look at the big brain on Martin. :laugh3:
Seriously, that was worded really well man. How go things with getting the business set up again after the move? If you need help...yell. I don't go back to work until January 9th. Until then...there are fish to catch and motorcycles to be ridden.

-Chris

I had a homemade leaf pack of 2 stock leaf packs (ala Rocklizard BB method), I wanted a little more so I added MJ shackles to get ~1/2" more. It stayed that way for a month or 2, now I'd say I have lost that 1/2" and maybe a little more due to the packs flattening out with the extra shackle length. I wouldn't add shackles to stock leaves ever again.

If you extend your bump stops when adding shackles then your leafs should be fine. I made my leafs look like W's from cramming them all the way to the factory 3" long bump stop multiple times.

Plan and simple.. Longer shackles will allow your leafs to cycle properly, which in turn will give you more flex and a softer ride.. Ive seen people with the old Auto Zone truck shackles bent to fit the XJ and those things are like 12 inches long

XTrmXJ said:

Ive seen people with the old Auto Zone truck shackles bent to fit the XJ and those things are like 12 inches long

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I dont have any problem with shackles, but forshizzle thats tooooo long!

Ive seen it, its not pretty, and even though they didnt use the last few holes, they still didnt cut the rest off... Ive also seen them on YJ running around here in Va.

A slightly longer shackle is a good thing, it can allow the spring back to move more freely at the extremes of compresion and droop. Any of the aftermarket extended shackles work well and won't hurt stock or aftermarket leaf sprigs. Those thinking the longer shackle flattened their pack are mistaken, when you wheel a rig and flex the spings to the max a lot of springs will fatigue, especially stock springs that are already used. All a longer shackle does is move the spring mounting point, which could also be done by moving the shackle mount down, which no one would say would ruin a leaf pack. The advantage of a slightly longer shackle is the better spring performance gained. If the shackle is too long, like 6" longer or more, then the angle on the spring has been changed too much, and there will be more sideways flex allowed by the shackle that can effect handling.

3"-4" longer shackles are good, even on stock springs. 12" longer shackles are lame.

The longer shakle moves the mount further out tword the rear. This WILL flatten teh leaf pack on a stock set. If the mounts move back, the springs will then flex to accomadate the move and in turn will dearch. You can't have the same factory arch AND move the mount back.

Yes, the ride quality stays the same or slighly better, due to the fact there is less arch and therefore less resistance to the spring absorbing movement. The down side is that less arch also means more flex of the pack and the ends of the main will dearch too much over time.

If you take even a stock setup out and flex it, you will see that the packs dearch. Now imagine how much more they will that there is even less resistance. Great for flexing now, but the packs will sag out even faster now.