Nothing wrong with radius arms. They have been used for 40 years on several vehicles. Now thats not to say the fabtech kit is good, as I have zero experience with their kit. But there is no reason to say radius arms suck unless you have some knowledge to back it up.

 

the radius arms arent bad, but the flex that the coilover provides is limited by the radiuas arm.......almost defeats the purpose. just buy two BB and stack them ontop of eachother...same results

 

A radius arm "rotates" the diff with the radius being the length of the lower arm. A four link system keeps the diff in the same attitude as it travels up and down. The twisting or rotation that the radius system does twists the main spring, shock mounts and all steering parts. Not good.
It is not the best system and I feel the 4 link is far better.

 

What greenmachine07 said.

I guess maybe for dune stuff where articulation isn't as important it'd be OK, but Fabtech markets the system as a "crawler" system...

 

nope, nothing wrong with radius arms if all you are looking for is big vertical travel like desert race trucks see. while radius arms have been used for 40 years, rock crawling and the demand for big articulation that we see today is still relatively new. and, if articulated travel is what you are looking for, by design, radius arms will limit your flex or at least by comparison to a 4 link design. does this mean radius arms won't flex? not at all. however, forcing radius arms to flex will put it's bushing in an extreme state of bind and this will cause them to fail quickly.

 

Interesting info... good to know... I had always thought radius arms were the better set up (my bro did a SAS on his bronco and used them...) Maybe for different vehciles they can be set up different ... cuz he BEATS on his rig and it still does exceptional in the rocks and tearing across the desert at high speed. Heres a pic of my brother proud of his flex

 

please don't misunderstand me. i never said that radius arms would prevent you from playing on the rocks or that they wouldn't flex. all i am saying is that they simply will not offer AS MUCH flex as a 4 link setup or at least, not without blowing out their bushing very quickly. radius arms provide a solution to the problem of how to go long arm. however, time and experience has taught us that IF you are looking for extreme flex, a 4 link design will do it better.

these are shots of my jk with 37's, EVO flex setup and if you can believe it, with teraflex short arms....







you can also see it in action here:

http://www.youtube.com/watch?v=sGmyyBhptZI

the silver 4-door is off road evolution's JK and they are running 40" tires and a full traction 4-link long arm kit with their EVO coilovers

 

...and as soon as we trim those fenders you'll have room for even more flex before you stuff that tire like that!

 

Radius arm suspension, Am I right to think that the bushings being in a bind is somewhat due to having two upper control arms pushing and pulling in opposite directions during articulation. Don’t some manufactures eliminate this by using an upper and lower control arm on one side and on the opposite side you would only have a single lower arm and no upper?

 

Look man its your jeep and if you like it test it out!! its most likely not going to fail you but it might not be as good as others its all from testing with trial and error
look dont other people bring you down
personal i think it looks sick and have seen it run a dodge straight axle trucks and it is awesome so im sure it will great on a jeep
any complete lift is going to be pretty good