Box sliders instead of shackles.

[Kane]

I thought of doing this many years ago to my CJ5 and now that I am building a CJ8 and replacing everything I started looking into them again. The total cost is not much more than buying new hangers, shackles and bushings plus they have alot of advantages. Stability is increased, no long shackle wandering issues. Range of flex is higher as well and I am goin gto run a flat wragler spring in SOA configuration. This will lower me down a bit and the end result would be about 3-4 inches of lift and a very smooth ride. I plan on buying Alcan or simliar SOA specific springs.

These do not hinder spring flex and the delrin bushing are self lubricated, very tough and inexpensive to replace. Plus you can convert to a bearing if you desire.

Anyone run them or know people that do?

Here is a thread about them on Pirate.
new parts delivered, leaf spring sliders/shackle boxes - Page 4 - Pirate4x4.Com

Here are some cheep ones I can modify if needed.
Speedway Standard Leaf Spring Sliders - Speedway Motors, America's Oldest Speed Shop

More expensive and off road rated.
Liquid Iron Industries Slider Box Kit

 

[Old Dog]

I've thought about these as well, but in my mind at least, I would think you would get less flex since there is no shackle up and down movement.
If you go that way let us know how they work for you.

 

[IOPort51]

I like this idea very much. a much better system than shackles by my estimation.

I like the liquid ones better as they restrain the downward as well as upward but I can not brag on the way they have the square stock welded on, there is not really and support in the direction of the force. If I was going to build these it would be with a milled slot in wide bar stock that was then welded to the box and I think I would want to trap the bearing block in a channel rather than just support it top and bottom.

I can see these being totally cool on a street car but so far I would say they have not quite made the transition to off road.

BUT, I think the Idea has a great deal of potential.

 

[csuengr]

To me it just appears to be a complicated solution to a problem that doesn't exist.

 

[IOPort51]

valid point.

One other thing to consider, ancient history, when 60 minutes declared the CJ5 unsafe because of roll over issues the part most often found failed was the shackle. It would seem that under extreme side load the stock shackle is prone to failure.

I can't help but think that a sliding mechanism, although more complicated, would eliminate the leverage of the side load and by eliminating the shifting center of load of the shackle system the ride could be greatly improved.

remember, very few modifications we do to our CJs are because things are broke. Most are just because we think we can make things better.

To me it just appears to be a complicated solution to a problem that doesn't exist.

 

[73CJ]

Interesting idea. Probably going to wait until I could see one in action.

Kinda like the extra travel the shackles give it as well.

The UHMW blocks are going to wear. The extra stress twisting the spring in a direction it really doesn't want to go = fatigue cracking

It just not going to move with less force than greased shackles = rough ride

Hummmmmmm

 

[Kane]

To me it just appears to be a complicated solution to a problem that doesn't exist.

Think of it this way. Stock suspension, I would agree, lifted, not so much. When a spring is arched, the more arch you have the longer the shackle needs to be in order to utilize the full ability of that spring to flex. The longer shackle becomes a leverage point against the hanger. It also creates a problem with caster that must be fixed with degree shims. Then when ever the angle of the shackle is changed like when cornering or braking, the caster changes with it and creates some wander. Also the longer shackle with flex from side to side and if the 2 bushings are slightly worn it will make the Jeep become very scary at highway speeds. There are tons of threads on speed related issues on this and all Jeep sites. Most of this comes from loose/worn parts and the shackle generally is the primary culprit. I haven't even gone into the related problems from a spring over axle swap.

So a problem does exist with a lifted Jeep on longer shackles. The box slider is not complicated at all. It is a piece of box tube with some slots cut into it with a sliding mechanism. The racing cars guys have been using these for years because the greatly help with traction on launch. These sliders remove the variable arch of a shackle and make the travel linear. The linear travel gives the spring a constant rate. The constant rate allows the tires to hook up much better.

My reason is different. I want a SOA lift without 5 inches of gain. I want a smooth riding Jeep that flats springs allow but only run 33 inch tires. By doing an SOA lift and using the box sliders I remove about 4 inches of shackle and about 2 inches of lifts. I should get an SOA lifted Jeep with only a 3 or so inch height increase and a smooth ride. The box sliders will help with wheel hop in the rear axle to a degree as well. With the soft springs and no variable arch the cornering lean issues will be reduced as proven by the racing guys.

 

[tarry99]

Think of it this way. Stock suspension, I would agree, lifted, not so much. When a spring is arched, the more arch you have the longer the shackle needs to be in order to utilize the full ability of that spring to flex. The longer shackle becomes a leverage point against the hanger. It also creates a problem with caster that must be fixed with degree shims. Then when ever the angle of the shackle is changed like when cornering or braking, the caster changes with it and creates some wander. Also the longer shackle with flex from side to side and if the 2 bushings are slightly worn it will make the Jeep become very scary at highway speeds. There are tons of threads on speed related issues on this and all Jeep sites. Most of this comes from loose/worn parts and the shackle generally is the primary culprit. I haven't even gone into the related problems from a spring over axle swap.

So a problem does exist with a lifted Jeep on longer shackles. The box slider is not complicated at all. It is a piece of box tube with some slots cut into it with a sliding mechanism. The racing cars guys have been using these for years because the greatly help with traction on launch. These sliders remove the variable arch of a shackle and make the travel linear. The linear travel gives the spring a constant rate. The constant rate allows the tires to hook up much better.

My reason is different. I want a SOA lift without 5 inches of gain. I want a smooth riding Jeep that flats springs allow but only run 33 inch tires. By doing an SOA lift and using the box sliders I remove about 4 inches of shackle and about 2 inches of lifts. I should get an SOA lifted Jeep with only a 3 or so inch height increase and a smooth ride. The box sliders will help with wheel hop in the rear axle to a degree as well. With the soft springs and no variable arch the cornering lean issues will be reduced as proven by the racing guys.

Those are all interesting points and I do believe the sliders may have some benefit in some cases and then again not in others....the option of lowering your COG with the use of sliders is a plus, as far as increased traction I would doubt that since nothing has really changed to eliminate spring wrap. Most who use a leaf spring in a racing application will also have some form of traction bar that is mounted in the same arch that doesn't allow the housing to rotate and wrap the spring up under acceleration.
Some say you can strap the leading leaves on the forward side of the rear end to control some of that , but that also changes your spring rate & flexibility.
Flex may also be challenged as the spring may not want to twist much inside that housing as it would with a shackle.
I have been using a shackle that is threaded and clamps the sides to the spring housing that eliminates some of the sway.
Lets face it , if one had there choice , leaf springs would probably not be used much anymore. The coil spring or shock combo does all the same functions that a leaf can do in a much smaller & more easily controlled package.

I think it's great that your thinking of trying these and I'm sure everyone's all ears to hear the results. Good Luck!

 

[PaRenegade]

To me it just appears to be a complicated solution to a problem that doesn't exist.

That's just what I was thinking. And it comes with the typical blame the shackle line of thinking.

IOport - Do you have any links to the report that showed the shackle failure as the cause? Seems to me I recall the issue was a combination of narrow track, high center of gravity that lead to roll overs; and of course driving it in a non typical way by making a sharp "J" turn in a vehicle not designed to. The Bronco II's also failed even worse in roll over tests around the same timeframe. I believe they had coil / I-beam suspensions.

 

[JR74CJ5]

I know this is a little old Kane, but wondering what you decided. And if anyone has done this yet.

Looking at that pirate thread today has me thinking...


~ Jr

 

[Kane]

I haven't done this. I had so much work to do to the frame and then the axles that this took a back seat. I want to get my Jeep built first. This is one of those can do anytime projects and I will wait until the Jeep is driving.