I did some testing thinking to help the community on a thread we had running last year where we were discussing where to put the flexy joints from your rear control arms, frame or axel. I said Frame, somebody say axel, we went back and forth but we never concluded anything.
So yesterday i was doing some testing on my Jeep front Antirock setup
20211120_123229 by
RAM RSM, on Flickr
and i took the opportunity to observe what the rear control arm bushings were doing and that thread we had here came to mind, so here are the results from my observations. You want your flexy bushings on the frame (assuming you have arms with clevite on one side and flex bushings on the other side), In this case we were discusing Core4x4 T3 arms, if you have Claytons or any other arms with flex bushings on boths sides it wouldn't matter, if you have JJ on one side and flex bushings on the other put the JJ on the frame as the the bushings at the frame do most of the flexy work.
This post is for the off-roaders. My setup is the Tier 3 5 link system in red. Now originally I installed the bars with the Johnny Joints attached to the frame. For my intent and purpose this is wrong. It's wrong in my situation for one simple reason. I need the flex of the Johnny Joints...
www.ramforum.com
So to save time from the entire read this is a copy and paste from my post#43 there
"Hi Red. bringing this from the past to show you where the bushings put out the flex. I was doing some testing today with my Jeep and the bushings happened to be there to show me how they react to one wheel drooping so i thought about this thread
20211120_123420 by
RAM RSM, on Flickr
20211120_123257 by
RAM RSM, on Flickr
My lowers arms are all Clayton overland+ with the Giiro bushings, the uppers are factory clevite.
So with one wheel droop:
Rear lower at frame side, look at how much that bushing is doing the work.
20211120_112547 by
RAM RSM, on Flickr
Rear upper Frame side, the lowers flex a lot more than the uppers but even then look at how the bushing is binding a little since clevite doesn't twist side to side like flex joints do
20211120_112431 by
RAM RSM, on Flickr
Now lets look at the axel side
Rear lower at frame side, there is a little flex there, but it's not the same as what we see in the frame. I'll say it's virtually nothing in there.
20211120_112637 by
RAM RSM, on Flickr
Rear Upper axel side, little flex as well.
20211120_112420 by
RAM RSM, on Flickr
The stock rear shocks on my Jeep were 22 1/8" extended, the current rears are 26" so they're literally 4" longer than stock. I'd think this is why mostly every other manufacturer out there with rare exceptions put the flex joint in the frame side.
Sorry it took me a year to be bothered enough to do the test
"