I've been looking at all the possibilities for my recently acquired XJ and of course the lower control arms are on the docket for me to replace. I have found SEVERAL options with differing price points as well as options.

I understand that most any of the aftermarket options are better than the stock design but, the main thing I have come across that I cannot find much on is flex joints vs heim joints and what the benefits are of running a dual flex joint, single flex/single heim, or a control arm with two heim joints would be.

Let me know what thoughts/opinions are considering I am not looking to get into any extreme rock crawling or anything, just a good DD with a bit more capability for days off. Thanks!

 

the heck is a flex joint? like a rebuildable johnny? heims aren't rebuildable but johnny joints (flex joint?) are. running joints on both ends will result in harsher ride quality but will last much longer. rubber bushings will fail quickly if you're constantly cycling the suspension to its max. for your case you should be fine running a joint on one end and a bushing on the other

should you go with a heim or a johnny? that comes down to preference. I recommend whatever is medium price point joint/bushing combo

 

I suppose a rebuildable Johnny is what I am referring as a flex joint. Are there differences in articulation or is it just rebuildable/non rebuildable and ride quality?

 

I've seen heims for steering more than for control arms, Johnny joints seem to be more popular for this application. I've heard people say that heims wear out quicker in steering components, can't really speak for control arms.

Like atmos said, flex joint on one end, bushing on the other will do you just fine.

 

I am one for perusing in my downtime and came across ruff stuff specialties website and they had the option for the dual heim joint control arms on their .250 wall lowers. So just figured I would see what the potential differences would be. Thanks fo the help.

Also when swapping from oem control arms to tubular lowers, how much tire clearance do you typically gain? Is it enough to go to a 10.50 width tire or is 9.50 about as wide as you can go without swapping wheels with more back spacing?

 

Found a pretty good deal locally on some 31x10.50s is why I am asking.

 

I ran 12.5" wide 33" and 35" tires on short arms. you should have plenty of clearance, but aftermarket short arm replacements probably wont gain any clearance (unless the kit specifies otherwise)

 

Sorry, should have stated different. I meant tire scrub clearance not ride height.

 

If you are at 0-3" of lift use WJ arms.

 

I am currently.. stock. looking for future plans and trying to decide what will be best for me down the road. Are the stock WJ arms plenty strong? Its definitely something I would consider. I am not really looking to make my XJ overly tall by any means.

 

any year range I need to look at?

 

i've ran rubicon express flex joints (super-flex/extreme duty) and now johnny joints. both are similar and both are rebuildable.
i do however, prefer the johnny joints.

and they don't use heim joints in control arms for very good reasons.

 

What are those reasons? Curious because I just installed long arms with heim joints frame end, there's a lot of guys on pirate that run them as well. I can always switch to a rebuildable joint, but wondering why you think they're bad? I've never had personal experience with them prior to these long arms(and track bar as well now), but from what I've researched they're fine in control arms.

 

they're not bad. I've ran both johnny joints and heims. I currently run heims everywhere, using a total of (6) 1.25" heims in my 3 link set up. love it, they never wear out and if you lube them up a bit they don't squeak (I don't recommend this style because there is no room for vibration to escape, but mines not a DD and I have some beefy mounts). all 7/8 heim steering and track bar too, which worked great when it was a street driver too and still have not worn out

johnny joints are serviceable, even though my RE ones required a special tool to rebuild.. was not a fan of that. in the end it comes down to preference, but if you look under an ultra4 car its alllll heims

 

That's what I've been reading, esp on pirate. Solid joints on both ends for a trail rig, while adding a soft bushing of some kind axle end will help dd the rig. The B Lee kit I have does just that. I have no doubt the heims will be strong enough, just wondering why he mentioned there's a reason they're not used, when a lot of kits have them.

I have 1 ton tre for steering in fabbing too, and if when those wear I was thinking of swapping over to heims then as well, to try both and see what I prefer.

On a side note, what are you spraying your heims with? Living NYS where they lay salt like no ones business, I'm going to need to spray frequently.