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  #1  
Old 07-28-2019, 03:32 PM
Rusty76 Rusty76 is offline
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Stumped. Rear Shackle Flip

Hey Guys
For some reason I cant figure this out. I cut out my old shackle bracket that had a massive dangerous body lift under it. Picked up 2x ford ranger shacker hangers and some stock wagoneer shackles. with the plan to do a flip and hopefully allowing me to use stock leaf springs and giving me 1 1/2-2.0 inch of lift to fit my 31 inch tires. Got the idea from a post on here. Seems smart and economical.

This is a tough one for me to explain being a noob. Bare with me.
Under its own weight with no rear hangers the springs arch all the way up and are pressed up under the bed. If I did mount the shackle flip with a 45 angled to the rear what stopping it from continuing and pushing passed the 45 degree and basically being parallel with the flat ground.

Couple factors that might be messing me up. Front shackles are cut not replaced yet and the rear shocks are super old. The rear lifts are still connected at the front and still bolted to axle.

I measured the leafs best I could Front 25.5x23.5x2.5, Rear 30.5x24.5x2.5
Stock is Front 22.5x24.5x2.5 rear 26x31x2.5
I realize the measurements dont match but I'm sure I was not 100% accurate
crawling around measuring.

Maybe I should just buck up and purchase a BJ lift kit but I would like to save some cash and focus on getting the drive train in.
Thanks for the help! It's probably obvious..

IMG_5397 by , on Flickr
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  #2  
Old 07-28-2019, 03:54 PM
SJTD SJTD is offline
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Join Date: Apr 26, 2012
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If I'm understanding your question the stiffness of the the spring keeps it from continuing back. The spring still has to compress for it to extend and the shackle to move.

The advantage of having the shackle pivot ahead of the spring eye is you get a lower effective spring rate.

The disadvantage is you can limit travel. If the spring wants to compress more and get longer but the shackle has moved to where its two bolt holes are in line with the front spring bolt you have a problem. The spring wants to flatten out more and get longer but the shackle won't allow it. Major bind.

I'd install it so the shackle is vertical or a little past with the vehicle sitting on the springs. Got some clamps? Should be able to clamp the hangers to the frame to get the position right.
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  #3  
Old 07-28-2019, 08:02 PM
Rusty76 Rusty76 is offline
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Ok thanks for the reply. I think I've got it?
I assumed the shackle to bracket bolt was loose so it could swing front and back. That's not the case. You torque that bolt down enough so it will hold the weight of the body up. Keeping the shackle angle at around 45 degrees with the body weight on it. When you hit a bump the spring flexes pushing the shackle out a few inches before it comes back to fixed position....

Man, does my explanation even make sense? Sorry if I don't reply right away. Just heading out on a 3 day rafting trip/ Jeep sabbatical.
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  #4  
Old 07-29-2019, 12:09 AM
SJTD SJTD is offline
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Seems like you were wondering about the shackle should be able to move with the bolt tight.

If you had urethane bushings it would move. With standard rubber bushings it shouldn't. The rubber is vulcanized to the sleeve which is held tight by the bolt squeezing the mount against the sleeve.

This is why you want the vehicle sitting on the wheels before tightening the the spring and shackle bolts. It puts the rubber in an unloaded condition in the normal riding position.

I'm wondering about the 45 degree thing. Where'd it come from? Why?
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'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.
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  #5  
Old 07-29-2019, 06:38 AM
Rusty76 Rusty76 is offline
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Morning.. The 45 degree shackle was just a general guess after its all bolted
Like this pictures. up.http://i998.photobucket.com/albums/a...ostest0001.jpg

As of right now both rear springs are bolted in the front and cut in the back.
the old shackle bracket are gone. the body of the wagoneer is basically sitting on those rear spring. sitting on its wheels.

So by tightening the shackle to bracket bolt it will hold the weight of the vehicle but still allow it to move that little bit once the spring is flexed.

thanks again
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  #6  
Old 08-07-2019, 02:29 PM
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bufurd bufurd is offline
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My opinion that pic is not how I would mount it, like said earlier, vertical (back a little bit okay) with the vehicle weight on it is how I'd roll. What you don't want is with the weight off (axle hanging) for the shackle to swing forward enough that it could lock forward.
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  #7  
Old 08-10-2019, 01:50 PM
Rusty76 Rusty76 is offline
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I agree. I've been looking and chatting a lot about the flip. I'm hoping to get this done next week. Pretty nervous about drilling into frame. Really going to take my time mocking it up. Thanks for the help.
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  #8  
Old 08-12-2019, 05:27 PM
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rang-a-stang rang-a-stang is offline
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I think the real angle you want is with the weight of the axle hanging on the spring, the shackle should have a tiny bit of a downward angle. If the shackle and spring go straight under full droop you will have a good chance of the shackle flipping upward when you the axle comes back up and getting jammed into the chassis.

just my thoughts.... can anyone correct me?
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  #9  
Old 08-14-2019, 01:50 AM
bagusjeep bagusjeep is offline
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With full droop (i.e. jacked up and dangling) the line between the shackle eye, spring eye and spring should not be straight.

If you did, it would be 50/50 which way it would go when you loaded it back up. However, there is another effect which is that as you approach vertical, the shackle is jacking up the weight of the jeep and this can lead to a wild ride.

The closer you get to 180 degrees, the greater the impact of a small further droop in the axle. I suggest you keep it below 90 degrees just because of the handling characteristics.

On compression the angle would be well below 90 degrees. I suggest keeping this above 35 degrees.

If your range of movement is between those parameters, you should be safe from flipping the shackle or binding the spring or getting strange handling characteristics. It just takes a bit of levering and measurement to check you have it in the right position.

Last edited by bagusjeep : 08-14-2019 at 02:03 AM.
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  #10  
Old 08-14-2019, 04:33 AM
wiley-moeracing wiley-moeracing is offline
350 Buick
 
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get 2 4x4 blocks of wood, about 12" long, jack up the rear off the truck so the springs are unloaded and have a gap to slide the blocks of wood in. Position the blocks so when you lower the truck back end down, the springs have enough room to slide the eyes backwards and still be on the blocks of wood. Lower the back down so the full weight is on the springs. Mark where the center of the spring eye is on the frame rail, this will be your starting mark where the shackle mount should be. You will be able to hold the spring mount up to the frame and locate it so you can see where the shackle will be angled, shoot for a 35- 45 degree angle rearward(depends on your load and use), you will have room for the swing loaded and unloaded. Mark you bolt holes and drill it and then mount them. Make sure both sides are the same, you may have to move one side or the other to make them match. simple and easy.
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  #11  
Old 08-14-2019, 08:43 AM
Rusty76 Rusty76 is offline
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This is a huge help thanks everybody! I'm just about to get started on replacing the front leaf bushing and shackles. After that I will tackle the rear. I will be sure to update this thread. Thanks again.

Quick question. When I move to the back shackle hanger replacement does a guy need to remove the shocks or can I leave them in and replace at a later date?

Thanks!
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  #12  
Old 08-22-2019, 02:49 PM
Rusty76 Rusty76 is offline
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Hello; Ok so I got my shackle flip done but of course something is not adding up.
(Shocker)... Anyway my angle I believe is ok but the old springs are basically flat.
Prior to the shackle flip I did purchase the original shackles. Maybe I need to use those. They are a little shorter compared to the ford ranger shackle and hanger set up. I have not torqued all the bolds yet. Are my springs just so old and worn that they are flat and I need new ones? Learn as you go! That is the truth!

Sorry for the dark pics.

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  #13  
Old 08-22-2019, 03:41 PM
SJTD SJTD is offline
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Shackle angle has very little to do with the spring curvature. They'd have to be way past 45* before you'd get any "wedging" effect that would cause the springs to flatten out when just sitting.

The shorter shackles might get you a little height since they'd sit more vertical but not much if any.

I don't like the angle, seems too much but if the springs are sitting flat they're prolly ok. Should be pretty good if you get new springs of the same length with some arch.

Howzit ride?
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'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.
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  #14  
Old 08-22-2019, 03:43 PM
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rang-a-stang rang-a-stang is offline
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How does it look when the axle is hanging?
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  #15  
Old 08-22-2019, 04:11 PM
Rusty76 Rusty76 is offline
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Thanks for the quick reply Rang. Here is some pictures with the axle lowered.
Much more spring arch and I would say shackle in a better position.
So does this mean the old springs are shot and I need to replace?
Thanks everybody.


IMG_5117 by , on FlickrIMG_5534 by , on Flickr
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  #16  
Old 08-22-2019, 04:19 PM
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rang-a-stang rang-a-stang is offline
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My vote is move the mounts aft. Try unbolting them and moving them so the 2 bolts in the back become the 2 bolts in the front. Then let it droop and check it again. If the shackle and spring still have some angle in then, finish mounting the mount. If the shackle and spring go straight, move the mount to the middle of those 2 places and call it good...

Wait for others to respond before you try my idea. I have never done this and am guessing. I think resting, the angle should be slightly more than what you have at full droop right now, but again, this is me guessing.
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  #17  
Old 08-22-2019, 04:20 PM
Rusty76 Rusty76 is offline
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Hey SJTD
Sorry missed your post. Not sure how it rides. The rebuilt engine, trans, transfer
are sitting idle beside the rig. I just wanted to get a bunch of stuff done, cutting, grinding, welding panels before I put everything back in. I'm actually getting close.
Man should have just cracked the wallet and bought a proper lift kit. I guess if the location of the shackle hanger is fine I'm only out the leaf spring bushing and my time. Which at this rate I could pay myself in pennies!

This rig had a huge death trap lift that I "fixed". I just want to get the engine in before the snow comes.
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Old 08-22-2019, 06:41 PM
wiley-moeracing wiley-moeracing is offline
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It looks like you have a slight boomerang type shackle? with the axle at full droop it looks right,( with the shocks installed?) The angle with a load on is not bad but you said the drivetrain is not in it? You need to have it fully loaded as driven so you can be more accurate with location on bracket. you may need to move it back a few inches when you have it fully loaded.
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  #19  
Old 08-23-2019, 08:50 AM
Rusty76 Rusty76 is offline
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Bummer I never even though about the weight of the driveline in before shackle placement! I agree at full droop it looks just about perfect. The old shocks are still installed. After I get the drivetrain installed I will most likely pick up stock springs or go with Rough Country 3 inch lift kit. I'm really looking for small lift to accommodate 31 inch tires. Not sure if stock springs and the shackle flip will do that for me? I've read mix reviews on the Rough Country set up but I can get it for under $1000 to my door. Being in Canada thats half the price of one of the more popular kits coming from US.

Actually now that I think about it the PO also had the shocks moved further up the axles and welded in big extensions to accommodate the massive lift blocks. Another job I will need to fix.

Well a couple more to do's on the wagoneer and I will get that drivetrain put in.
Enough rambling on and on...

Thanks
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