Shackle-less suspension

I am working on an almost all stock 1970 CJ-5 that a previous owner tried to lift with what appears to be a combination of aftermarket leafs and a homebrew shackle reversal. I believe the leafs to be 4" over stock, and the home-made shackles are probably adding at least 2", maybe 3" over stock. The thing just plain sits way to high. You may be able to see what I'm talking about in my avatar by looking at the distance between the top of the front tire and the bottom of the fender. Those are 33" tires in the picture. It seems to be driveable, but I just don't trust the setup. I want to make it safer, but still gain a little tire clearance over stock.

I would like to try to keep the leafs because I think they actually ride pretty nice, but I want to ditch the shackles. Has anyone ever tried a shackle-less front suspension? I am considering removing the front spring's reversed shackles and welding in frame mounted perches. The front springs would just bolt to solid mounts. Is this possible, or is the shackle essential? I've never built a CJ before, but I know of other older vehicles with leaf setups that don't use a shackle. My hypothesis is that keeping the front springs anchored to the frame would help keep steering tight.

The springs aren't too rigid, so I don't think it would create a rough ride, but is there a safety issue I'm missing here? For the rear, I would keep the reverse shackle, but mount my own beefier design out of 1/4" plate with a much shorter height, probably right around OEM in length. This should bring my overall lift to about 4", maybe 4.5" max in order to run 33" tires mounted on 10" rims. Any other inputs/ideas?

 

As a spring flexes, the horizontal spring length changes, hence the need for a shackle. An arched spring has a vertical and horizontal length. When the spring compresses, the vertical length gets smaller, thus forcing the horizontal length to increase. Theoretically, if your spring was perfectly flat, wheel travel would cause the horizontal spring length to decrease. If you had no shackle, there would be no way for the spring horizontal length to change and there would either be no wheel travel or the spring would buckle. Neither is good. Some older vehicles (as you mention) had no shackle, but had a slot for the spring to slide in as the length changed. Many heavy duty trucks still have that setup.

 

On an off road vehicle of fairly light weight, shackles are important. They keep the springs in alignment and allow fore and aft movement of the spring eye in relation to the frame. You have probably seen "slipper" springs that rest with the flat side to the frame, and the end is held usually inside a boxed tube. The problem is if you ever want to use the Jeep offroad, when going over bumps you could unload the front end enough for the spring to come out of the tube. this would probably result in a really loud crunching, grinding, screeching noise and a sudden hole in your wallet.
Good Luck
Tim

 

Okay. Thanks for all your responses. I think I am going to go with shorter shackles, then.

 

How long are the shackles from center of one hole to the center of the other? Your avatar doesn't look like a 4" lift and your shackles, well you really can't make out in the picture. Take a close up of the setup where we can see the shackles and the lift.

 

Ever thought of stockcar sliders???

 

These were talked about in the past and it seemed the problem with them was durability due to dirt/mud getting in them and wearing them out prematurely.

 

Holy crap I've learned so much about JEEPS since I posted that question; it almost hurts to read it. Amazing how much this site has taught me in such a short time.

I ended up welding and cutting that suspension out 3 times before I finally got it right. I am a firm believer now in just making your own H shackles to the exact length you need, up front where the factory put 'em, with nothing softer than polyurethane bushings (I think mine are somewhere around a 65 on the hardness scale).