Shackle Reversal Kits

[Tim]

I just bought an "83 CJ7 and I have been looking into doing a shackle reversal. I have been told some conflicting things about the advantages/disadvantages of this. My CJ is used as a daily driver and does not see aggressive trails (the most aggressive thing it will see is hunting trails in MN). So, I am wondering if I would get a large benefit out of the shackle reversal, would it greatly improve its ride on the road? If you have any other suggestions for improving its ride without harming its off road ability much, I'm all ears. Thanks for the help

 

[BusaDave9]

Now-a-days there are a lot of people that think shackle reversals are the way to go. I disagree. The problem with a shackle reversal is the axle moves too far to the rear as the vehicle goes over a bump. Some argue that a shackle reversal is better because the front tire goes back as you plow over an obstacle. Well almost all factory suspensions are made to go up and down without much front to rear movement to the front axle. If you have a lifted leaf spring suspension then the axle will move much farther forward as you compress the suspension. If you also have a shackle reversal then the axle will move much more to the rear than any factory suspension. I say this axle movement to the rear is a bad trait of a shackle reversal.
There are a lot of people on the internet that will say a shackle reversal is the best way to set up a leaf spring suspension. Many of these people are also selling a shackle reversal. I'm not saying they are lying. I think they are making shackle reversals because they think they are a better setup.
Almost all suspensions try to keep the axle moving strait up and down as the vehicle goes over bumps.
We had another thread on shackle reversals:
http://www.jeep-cj.com/forums/f19/shackle-reversals-3662/

 

[Old Dog]

I have a buddy with a CJ8 that put one on, he took it back off about 2 months later.

 

[coldwater]

Another loaded question! This is another one of those things that brings the fight between camps. I have only one friend (in my little corcle of jeep buddies) that installed one. I did drive it, and found it to be no diferent, and no better. I don't know how or where reversal kits got started, they just kind of showed up one day, and there they were. Dispite the finger wagging about the superior nature of them, there isn't any actual proof of it that I have ever seen. No better off road, no better on. No added component life, no worse component life. No better ride, no worse ride. Just more money. I almost think It's one of those things where someone looked at a Jeep and said, hey....arent those things on backwards?? let's swap them to look more conventional. I look at it this way. The Jeep was made by better men than I, and it's success can't be argued with. It has historically been untouchable off road, and any one i have had, has taken me anywhere I want to go, and when it gets stuck, it aint because of the shackles being forward! I'm not into changing stuff for the sake of changing stuff. I have to know it's measurably better, and appropriate for what I will need before I tear into my old CJ.

 

[BusaDave9]

Yes this is a hotly debated topic and since everyone has a right to my opinion I will put my two cents in. If you don't have much of a lift and the leaf springs don't have much arch to them then a shackle reversal wont' make much difference. But if you have a lift the front axle will move back quite a bit as you go over bumps. For that reason you will need a long travel drive shaft. I have a shackle reversal from the previous owner and this has caused quite a few problems. My drive shaft was bottoming out and banging into my Transfer Case . I had my drive shaft replaced with one with a long travel slip joint. It still bottomed out and I replaced it a 2nd time with one with 8 inches of usable travel (more than enough). The front tires were also smashing into my fender and I had to do a lot of metal cutting to resolve that.

In the above picture my tire is pressing into my inner fender. If I were to turn my wheel to the right it would press very hard into my nerf bar.
Although I already cut my front fenders before the above picture was taken I had to cut them some more. The nerf bars had to go. I then got rock sliders.
Here is a more recent photo.

You can see that the front tire moves far to the rear as the suspension compresses. This is the biggest problem with a shackle reversal and why I to make other modifications to keep my jeep from damaging itself going over bumps.

 

[coldwater]

Yes this is a hotly debated topic and since everyone has a right to my opinion I will put my two cents in. If you don't have much of a lift and the leaf springs don't have much arch to them then a shackle reversal wont' make much difference. But if you have a lift the front axle will move back quite a bit as you go over bumps. For that reason you will need a long travel drive shaft. I have a shackle reversal from the previous owner and this has caused quite a few problems. My drive shaft was bottoming out and banging into my Transfer Case . I had my drive shaft replaced with one with a long travel slip joint. It still bottomed out and I replaced it a 2nd time with one with 8 inches of usable travel (more than enough). The front tires were also smashing into my fender and I had to do a lot of metal cutting to resolve that.

In the above picture my tire is pressing into my inner fender. If I were to turn my wheel to the right it would press very hard into my nerf bar.
Although I already cut my front fenders before the above picture was taken I had to cut them some more. The nerf bars had to go. I then got rock sliders.
Here is a more recent photo.

You can see that the front tire moves far to the rear as the suspension compresses. This is the biggest problem with a shackle reversal and why I to make other modifications to keep my jeep from damaging itself going over bumps.

Dave, great documentation listing the actual problems such a modification can lead to. it's hard to ignore when actual real world pictures in the first person experience are laid out for everyone to see. As I said before, I simply see no reason to reinvent the wheel (so to speak) for the sake of making a change. Especially when there is such good evidence showing poor results.

 

[IOPort51]

I don't have a dog in this fight but I would have to think that the amount of lift would be the deciding factor. I don't think I would even consider it until I had a SOA. and was experiencing major bump steer problems.

 

[Old Dog]

IO it's funny you say that, because I believe that if you have a soa and flat springs than a reversal will work. Thats because with flat springs the tires will not move rearward anymore. But I still don't like them myself.

 

[coldwater]

Correct. The springs will then move up and down as designed. Now go add a lift spring to the mix, and we're back to square one, but on a taller jeep.

 

[LongHorn]

Leave it me to be on the other side of the argument, but I've owned a lot of Jeeps.
I had never tried a shackle reversal, never saw the need.
On my current rig I had decided to go with full width D60's.
I found a deal on a Blue Torch Fab full width spring reversal kit on CL.
So that's the way I went. I enjoy the fact that it takes expansion joints on the freeway a lot better now. Also it does not hunt back and forth in the lane like a lot of Jeep CJ's.
Now I'm running about 12" inches of lift with 38" tires and yes I guess the back of my front fender is the travel limit, but that's at fairly extreme travel as you can see in my album. I suppose I could easily remedy that by going with tube fenders.
As far as suspension design goes Chevrolet and GMC made a lot of trucks with the same setup. I seemed to work very well for them for a lot of years.

 

[mylittlecj5]

I'm with you LH...Don't feel alone over here on this side!

My '74 has a possibly homebuilt (not by me) Shackle reversal on it. I love the way it drives on the hideous roads we have here in Oklahoma. Even with 6" of lift, it rides better then my old stock CJ7 did on Las Vegas roads.
When I got the Jeep, I did have to modify the fenders for clearance, but I still run (what looks like) the stock front driveshaft, and it has never had a problem with hitting the Transfer Case , no matter how hard I have bound it up.

 

[73CJ]

LH I would have to agree. One of the better things I did to mine. I don't mind running it on the street now.

8" travel Tom Woods - no problems.

 

[CJ]

LH I would have to agree. One of the better things I did to mine. I don't mind running it on the street now.

8" travel Tom Woods - no problems.

Are you running SOA or SUA? I have found that SOA work great with reversals as the lift negates the need to trim.

Most who like reversals are SOA so they don't have the problems that SUA have...

 

[IOPort51]

Tim never tells us if he has any lift. So it would seem that he would like the mechanical bull to ride like a new Caddy, good luck with that Tim.
are we agreed that the shackle reversal is a good thing for major spring lifts but perhaps a waste of time for those of us not pursuing the path of well engineered insanity??
Busa dave, where did you find rock rails for the CJ5 ??

I just bought an "83 CJ7 and I have been looking into doing a shackle reversal. I have been told some conflicting things about the advantages/disadvantages of this. My CJ is used as a daily driver and does not see aggressive trails (the most aggressive thing it will see is hunting trails in MN). So, I am wondering if I would get a large benefit out of the shackle reversal, would it greatly improve its ride on the road? If you have any other suggestions for improving its ride without harming its off road ability much, I'm all ears. Thanks for the help

 

[BusaDave9]

Busa dave, where did you find rock rails for the CJ5 ??

I had them custom made. It is very hard to find rock sliders for a CJ5 but with the fender cutting I did there was no other option but custom made.

 

[BusaDave9]

I have found that SOA work great with reversals as the lift negates the need to trim.

I agree. There are a lot of pickups that come from the factory with SOA and the shackles in the rear. You'll also notice those leaf springs are almost strait so as the suspension compresses the axle will go up and down without moving to the rear.

 

[73CJ]

Are you running SOA or SUA? I have found that SOA work great with reversals as the lift negates the need to trim.

Most who like reversals are SOA so they don't have the problems that SUA have...

M.O.R.E. SR w/ SUA and 2-1/2" OME springs. It just tracks so much nicer now. Lets face it, there is asphalt between most trails.

 

[BusaDave9]

M.O.R.E. SR w/ SUA and 2-1/2" OME springs. It just tracks so much nicer now. Lets face it, there is asphalt between most trails.

I think there are times that a shackle reversal can help a jeep track strait without wander back and forth. I think this is due to movement at the shackles maybe due to worn bushings.
If the shackles are in the front of the axles and there is any side to side movement. then the front of the springs would move slightly side to side. Since the steering linkage is also in the front of the axle and the steering gearbox is mounted solidly to the frame then slight movement of the front of the springs will translate to slight wander back and forth in the lane. This has to be counteracted by the driver.
If the shackles are in the rear of the front springs and there is any movement then it will have less of an effect on the steering. Now the front of the spring has a big bushing holding the front of the spring more solidly to the frame. Since the steering linkage is here at the end of the spring that is more solidly mounted then it is less likely to produce a wander back and forth across the road.
This is one reason people that install shackle reversals say the vehicle is more stable afterwards. But I think new shackles and bussings would have also fixed the issue. I don't think the jeep had the wander issue when it was new.
I once drove a flat fender that had a horrible wander. It was unsafe to drive over 40mph. While sitting still you could move the steering wheel back and forth before the wheel would steer to the side. The free play was actually coming from the front shackles. As you would turn the steering wheel you were actually moving the front axle to the side before the wheel would turn. If this owner would then install a shackle reversal he would say that's what fixed his stability problem. But I would counter that new shackles and bushings would have fixed it too.

 

[73CJ]

I enjoy the fact that it takes expansion joints on the freeway a lot better now. Also it does not hunt back and forth in the lane like a lot of Jeep CJ's.

A modest 6" lift with 38.5's, Lornhorn hit the nail on the head. 8" slip on the front drive shaft - Tom Wood's. No problems so far. Make sure you measure it correctly.

Tube fenders - How much clearance do you need?

 

[CJ]

A modest 6" lift with 38.5's, Lornhorn hit the nail on the head. 8" slip on the front drive shaft - Tom Wood's. No problems so far. Make sure you measure it correctly.

Tube fenders - How much clearance do you need?

Again - drive line measurements done correctly, Tw drive shafts - you handled it by the book.