Boomerang shackles ....thoughts??

This is nothing to do with Jeeps specifically, it would be the same on any other vehicle with a Panhard (I don't own a Jeep, never have). It's all about the type of bolted joint.

The bushing is meant to be bolted between two plates so that the bushing sleeve and the bolt are both loaded in shear (instead of bending) on both ends. That's what "double shear" means. It looks like the other end of your Panhard is attached this way. The leaf spring shackles are another example.

In single shear, the bushing and bolt are loaded in shear on one end only. This totally changes the loading on the bolt and the bushing sleeve, and there can be significant bending and tensile load components as well. The bolt is not necessarily sized for that, because the bolted joint was designed loading in double shear without the additional types of single shear loads. The bushing sleeve is not sized for that either, and would have a larger diameter where it mates to the plate if it did.

The Panhard end and bushing of that type was also designed for double shear, and the only thing keeping your Panhard end from coming off of the bushing is that relatively light duty fender washer. The axle isn't going anywhere if that happens, because the leaf springs will still locate and retain the axle laterally, but it could be a pretty sudden change in steering or whatever if that happened at speed on the street.

So I'm not saying that your Jeep is going to fly apart and kill you, but I think that it needs to be redone properly. If you're going to take an existing joint design and put it on your rig, it needs to be done right for it to perform correctly.

At the bare minimum, change that silly fender washer out for a heavier retainer plate that isn't going to turn into a cone if it gets loaded. Heck, the same parts (washer-type retainer plate) on the four rear lateral link bushings on my Subarus are at least 3 times thicker than that, maybe 4 times.

Here's an example of a double shear Panhard bracket from Google:

aimage.fourwheeler.com_f_26698417_w660_h440_q80_re0_cr1_ar0_104719bc9b88ad6c977b04b243b55e76c4.jpg
 
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Question? How effective is the panhard bar on a leaf sprung setup? Could he just remove it and then not worry about a double shear bracket? Maybe he would gain down travel.
 
powerstrokin04 said:
Question? How effective is the panhard bar on a leaf sprung setup? Could he just remove it and then not worry about a double shear bracket? Maybe he would gain down travel.
Click to expand...

You can run without a Panhard with leaf springs, but that doesn't mean you should.

This will induce a large amount of steering play when the wheel is straight.

When you turn the wheel slightly, not only will the tires turn some, but the axle will shift side to side slightly, in the opposite direction of steering input.

I would not recommend this on a rig that sees much street use.

I currently run without a front Panhard, and my front leafs are 3/4" not parallel to help keep the axle centered. My leafs are flat with Poly bushings everywhere, and my front axle still moves side to side.

Being that my rig is on the road 2%, I deal with it, but understand that it needs a Panhard.

I would make sure everything else is cycling correctly before eliminating it.

As far as making that bracket double shear, think of using a piece of c channel instead of flat plate
 
I would say just remove the track bar/panhard. My YJ does fine on road and at highway speeds without it. As long as your suspension is solid, the leafs will be sufficient in keeping the axle centered.
 
Only the first 20 seconds of the video play when I watch it, so I can't really give a good opinion.

Your suspension would allow for more drop if your shackles had more angle to them.

Like this picture I found on google:
aimg.photobucket.com_albums_v633_atom631_rear_shackle_after.jpg


MANY leaf spring front suspension vehicles did not come with panhard rods.
 
Well I drive it on the street alot and right now it drives great! I don't want to remove it. Double shear is clearly not the factory method to mount that and I don't see a option to buy a double shear bracket for it. I guess I have another project for Marsfab......thanks for all the info!!!!!
 
The main problem is see is not so much single shear, but that it's just a flat plate with one bolt. It can act just like a spring shackle letting the Panhard move left to right.


The main thing is make sure the shackles can move, and ditch the sway bar for sure.
 
When I got the jeep it had the three stabilizer on it, it drives so good I just left it. Had an alignment done two months ago...
 
drkelly said:
Only the first 20 seconds of the video play when I watch it, so I can't really give a good opinion.

Your suspension would allow for more drop if your shackles had more angle to them.

Like this picture I found on google:
View attachment 222056

MANY leaf spring front suspension vehicles did not come with panhard rods.
Click to expand...


But more shackle angle will require longer springs, which would certainly help with flex.
Bolt some 63s on there and she will flex like a romanian gymanst
 
Have you tried simply jacking up one wheel from the frame in the driveway?

Whats limiting you should quickly be evident.
 
Yea it looks like as soon as the shackle goes straight it stops, it looks like the spring is just stiff, sounds like the boomerang shackles will not help so I will just wheel it like it is. Thanks for all the help..
 
krehel24 said:
Yea it looks like as soon as the shackle goes straight it stops, it looks like the spring is just stiff, sounds like the boomerang shackles will not help so I will just wheel it like it is. Thanks for all the help..
Click to expand...

Just add a thicker retainer plate on the outside of that panhard end to replace that flimsy fender washer. Then go wheel it.
 
Will do!!! Thanks again!

Maybe it would be best to bend some 1/4 steel and weld it to that to make it a double shear....
 
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Having the track bar on a YJ will definitely limit your flex. That was one of the first things I threw out when I had my YJ. Ran no track bars, no sway bars, spring over on my Yj and daily drove it hundreds of miles a week for two years. You have a very limited range of flex with the track bar attached because the track bar is trying to travel in an arch and pull the axle to the side while the leafs want to keep the axle moving straight up and down. The jeep may handle a little different, but you will get used to it quick and you will notice a difference off-road.
 
Think of all the Cj's running around with no track bars. IMO, you can take them off and not see too much ill effect. You will gain a ton off road though. I have driven YJ's with sway bars off and track bars off with not much problem. I would keep the sway bar with some disconnects for off road and ditch the track bar. In the end, it's easy to remove. Put it back on if you don't like it.
 
I've read this whole thread, I have experience with YJ's but not too much else honestly...
I say start by removing the track bars front and rear as well as sway bars. Ive commuted 45 mi round trip for months to work and back and from Boone to Greensboro while in college with two different YJ's set up spring under axle and spring over axle. I ran track bars for a month then threw them away cause they are just not necessary. (never ran a sway bar)
Like someone else said, Look at all the CJ's, toyotas, scouts, etc that do not run them…
This should help some, but another issue is that it looks like you are running a 2" lift shackle and maybe a 2" lift spring to achieve your 4" lift. A true 4 inch lift spring and a shorter shackle will allow your springs to flex upward, pushing your shackle forward and allowing for more flex. Your springs are flatter and when pushed up on by the axle, are not pushing forward on the shackle.
its late, mucho :beer: hope that makes sense:confused: haha
 
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