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I wouldn't expect any thing more from a state student.:flipoff2: After spending time there for my undergrad and masters I am glad to be heading some place else in Jan. At least you are asking. From the looks of the recent posts you have your hands full.
 
Yea, yea, on a more serious note thou, what is the difference between a johnny joint and a flex joint? And why does polyperformance not have any flex joints with studs on them?

Also Jon I pm'd you I need to get some parts from you for my buddies k5 that im doin high steer on and we're kinda in a hurry (tryin to get it done in time for the Big Daddy event), give me a call back when you can call at any hour no biggy, thanks.
 
yea see those look exactly like the johnny joints listed in poly performance

seriously poly performance hasl like 5 different things that look exactly alike yet they are all classified differently???

Makes it kinda confusing as to wtf each thing is for.

The johnny joints, flex balls, rubicon balls, and uniballs all look like the same thing with minute differences.

Can someone please just explain to me what the difference is between them all and which ones flex better and which ones are strongest.

Oh also what do high misalignment spacers do?

Also where does a heim joint fall in flex and strength wise with the above listed stuff?
 
Johnny Joints will be the best for flex at 30 degrees of misalignment. All the others fall in around 22 degrees. It is not really that big of a deal if you are using them on both ends. If it is still streetable then you will probably want a poly bushing at one end to help with shock loads. I would run the JJ, RE joints, or the large flex joints. The new Johnny joints are available with a cast in threaded rod as opposed to a welded on bolt. They look like a much better setup. What it really comes down to is who do you want to support? You are not only buying the ends but also rebuild tools, rebuild kits, and probably tube adapters too.

edit: forgot about heims.

heims are another solution. I don't often consider them because they are not rebuildable and must be replaced. Misalignment is around 22 degrees and they require misalignment spacers. I believe that with high misalignment spacers you can get a few more degrees out of them. A good heim joint will run you as much or more then the flex joint and you can't rebuild it when it gets loose. Lots of people run them and run them for years, but for my money I want something that is rebuildable.

Strength wise you would have to look up the numbers but most are in the 20,000lb range and up. From my experience the welded on threaded rod fails before the joint does. This fails after the link bends, and before the axle wraps around and destroys the steering, driveshaft, and shocks.
 
Thanks man, that clears things up a good bit.

The application for me is the f100 which is a trailer queen so im not worried about streetability just strength and performance.

The way I'm wanting to sett up my suspension is:

-on one side a radius arm of sorts using the evolution joint at the frame, then a 2.5" currie JJ w/ thread for the point the top shoot off of the radius arms connects to the axle and a 3" Currie JJ w/o thread at the bottom point that the radius arm will connect to the axle

-The other side will be a single link evolution joint at the frame 3" currie JJ w/o thread at the axle.

I want to use .5" wall tubing so the tube for the evo joints will have to be 2.75" OD tube and the tube for the upper link for the 2.5" Currie JJ with threads will have to be 2.5" OD Tube to fit the threaded adaptors for each.

What do you guys think about that setup? I realize that it is expensive way to go but I want to seriously be able to bash the truck with blatent disregard.

Thanks
 
I see no need whatsoever in going with tubing that big. I'll show you mine when I get done in a few weeks, but I'm going with 2" and 1.5" DOM all by .25" wall. If you're wanting to be able to bash the hell out of the truck, I'd say go with 2-2.5" chromo tubing by .25" wall. If you break that, you've probably ruined a lot more on your truck in the process haha.

I think you are talking about doing the same thing I am in the process of, so let me know if you want any visuals in the next little while.
 
Here's basically what I'm wanting to do attached below, reason for big tubing is cause down and dirty seems to be having trouble with .25 wall tube and my ford is pretty heavy, plus I like to be extremly heavy with my right foot so I would rather overbuild than keep replacing stuff.



aimg.photobucket.com_albums_v674_jrraw23_FordSuspension.jpg
 
why are u usig so many different joints ... keep it simple that way u dont have to pack the garage when u go wheeling . i run all 1 1/4 heims all right hand thread
i would also run that radius arm on both sides... i see those break when only using one
 
I would agree that you should just run with all the same joint. I have seen the radius on one side hold up well, but if and when it does let go it trashes a lot of stuff. That is why I went with a 4 link. If one link snaps I can limp out and hopefully not trash anything else.
 
I def get the idea of one joint making it easier to maintain, only thing is I don't need an adjustable joint at the axle except on the upper radius arm link. If i were to go all one type of joint then my best bet would probably be the currie 2.5" joints because they come in both adjustable and non adjustable sizes (the 3" currie joint is not offered with an adjustable thread). The next question would of course be will they be strong enough to hold up?

Also where exactly is the weak point of this setup? The single link? Or where the top part of the radius arm joins to the main tube?
 
The problem with that setup isn't that there is a weak link, but that single point catastrophic failure is built in. If anything breaks you are going to see major carnage. Remove any one joint or link in the front end and watch what happens.

Dual radius arms like that (with the upper and lower link in the same vertical plane) work well on the road, but will limit your flex and bind up on you

Down&Dirty is saying with a triangulated 4 link if he looses a link (top or bottom) he can at least get the rig to a location where it can be worked on, or back on the trailer without destroying the driveshaft, coilovers or other pricey bits.
I've seen both work well, but a friend ran the 3 link for a while and when he rebuilt his buggy went to a 4 link. There was no question.
 
makes since, I can see how if it broke id be severly limping afterwards, thats kinda why i wanted to beef it alot to not have to worry as much about it happening. I'm gonna be doin this on the rear axle so if it broke I wouldnt have to worry bout it messin up the steering fronts gonna be leafs for simplicity and durability.

I've also seen rigs flexing with the radius arm on one side and single link on the other and the flex is almost as good as any other coil setup I've seen.

Also the simplicity of the setup is good too, tryin to calculate the 4 link stuff is gonna suck especially cause i don't know my rigs corner weight and center of gravity etc, etc and have no way of weighing it to find out.

I mean worse case senario i see is something in the rear breaks the frame can sit directly on the axle and still roll around to get it on the trailer or w/e if I need it to.
 
It's a poor design front or rear but it's easy to use. It's especially poor in the rear because A, it's weak and B, the geometry is totally wrong. A 3 link with panhard (using 3 separate links) is not the same as a radius arm 3 link. Nor is a wishbone 3 link. I'd like to see the pbb thread that has anyone in agreeance with running rear ra's... Just not a good idea.
 
I don't see how it is weak, the radius arm side is literally a frikin traction bar, other side is a single link yes, but thats why I was wanting to build it super big to handle it.

If the geometry is so wrong why do all the bronco dudes run it very succesfully? I mean I realize its not gonna flex as well as a 4 link but from what I've seen it flex's plenty enough for me, im not tryin to build a super flexy rock buggy more of a stout all around truggy type deal that i can bounce off rocks, trees, steel reinforced concrete walls, ya know the usual :driver:

Here's the link below, notice the ones that had bad things to say about using the wristed radius arm in the rear were talking about the stock C bushings and the suggested solution was to do the setup i described above.

Also the other issue was having it dive or something like that under breaking on the road - not an issue for me, the ford will not see any road action trailer only.


http://www.pirate4x4.com/forum/showthread.php?p=415252
 
jrraw23 said:
II mean I realize its not gonna flex as well as a 4 link but from what I've seen it flex's plenty enough for me, im not tryin to build a super flexy rock buggy more of a stout all around truggy type deal that i can bounce off rocks, trees, steel reinforced concrete walls, ya know the usual :driver:
Click to expand...


build it just like you did that stinger and all will be well with the world
 
The bronco guys are running it in the front. I thought that is what you were working on. In the rear do a triangulated 4 link with adjustability built in. As long as you get it close and leave the links adjustable as well as a little adjustability in the mounts you can dial it in. It is not a big loss if you have to cut off some frame mounts and start over. The major cost is the link joints and as long as your links are a resonable length you can rebuild the mounts and get things right. You could even go with a wishbone 3 link and get good results.

I have been having problems with my front not the rear. Sure the rear links are bent but not bad enough to take me off the trail. The fronts were bending because during a big drop you smack the links as you go over the edge, then you put all the weight impacted on them when the front hits and the back tries to go over. The 2.5 flex joints have never been a weak link for me. Also any link end can be made adjustable. You just pay someone to weld on a stud.
 
I think the main problem with that type of setup in the back is the torque load on the tubes. Yes it is essentially a traction bar except that the traction bar is strictly for antiwrap where this will have additional load from being used to locate the axle. The tracbar also has help from leaf springs to reduce the load, but some times they still rip off. It also puts all of that rotational energy onto a single axle tube, and with they way they already spin that is more trouble. In the front the loads aren't as bad since the rear usually provides most of the power. I think with a heavy right foot, welded in tubes, a trussed axle you could still mess up a housing putting all of that power and expecting a single radius arm to hold it.

The thing to remember is that all the traction of an aired down off road tire translates back through the suspension. For a little more effort, a little more research, and a little more building you can run a setup that is proven to handle the loads. Not that a 4 link is the only way to go. For simplicity you could go to a wishbone 3 link and remove the tracbar.
 
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