Anybody have any good ideas for building a set of front lower long arms... Johnny Joints? Tubeing thickness? I need a stonger set than the ones I have due to running the arms over rocks, they bend after a couple of hits.. Anything would be good!

Thanks...

As I understand it, most of the mass produced long arms are .250 wall chro-mo. If you want stronger, go with thicker walls or larger OD and the same wall thickness. I prefer the RE cartridge style joints over the Johnny Joints because of the threaded plate holding it all together rather than just a snap ring. PSC sells some bushings pre-mounted on a threaded stud that would work great on one end (cuts down on the noise and vibration transferred to the frame) with the RE style joints on the other end.

Who is PSC?

Do you have a tube bender?
I have seen a several that tuck up high and then bend down to clear rocks.

PSC = http://www.spydercustoms.com/

Another good source for parts and tubing is http://www.bluetorchfab.com and http://www.polyperformance.com

Nope no bender, would love to have one but no room...

As I understand it, most of the mass produced long arms are .250 wall chro-mo. If you want stronger, go with thicker walls or larger OD and the same wall thickness. I prefer the RE cartridge style joints over the Johnny Joints because of the threaded plate holding it all together rather than just a snap ring. PSC sells some bushings pre-mounted on a threaded stud that would work great on one end (cuts down on the noise and vibration transferred to the frame) with the RE style joints on the other end.
Actually most are .120 wall. Not even chromolly. Chromolly is way too expensive.

Actually most are .120 wall. Not even chromolly. Chromolly is way too expensive.


Whose arms are .120 wall?

I will be useing .250 wall.

Actually most are .120 wall. Not even chromolly. Chromolly is way too expensive.


Well, some short arms are, but all of the long arm companys use thick tubing.


Rubicon Express uses 4340 Chromo 2.0" o.d. .250 wall

Rockkrawler uses solid stock 1.5" od

Full-Traction uses 2.0" od .250 wall D.O.M.

Fabtech uses 2.0" od .250 wall D.O.M.

claytons uses 2x2 .250 wall square tubing

Toys By Troy uses Heat Treated 7075 Alloy


I dont see any .120 wall in there??


the short arms are usually .140 wall

sometime you will see the upper arms at .120 wall, but rarely

I am also making my own long arm susp for my TJ.

I will be making the arms out of DOM 1020 2.5" .5 wall.

The cartridge joints will be the Summit machine sold on pirate 4x4 by Poly Performance, Mad4wd and PORC. Summit also made the RE joints in teh past before RE bought their own tooling.

Plan on buying the mounting brackets and truss from Claytons.

What are cartridge joints?

Do you have a tube bender?
I have seen a several that tuck up high and then bend down to clear rocks.

Gotta love long arms that look like this (http://www.nthdegreemobility.com/images/LA4-1.gif) and this (http://www.nthdegreemobility.com/images/LA1.gif) :eek: ... Here (http://www.nthdegreemobility.com/SuspensionSystemPictures.htm)'s the website. ... not sure about those "gyro"-joints though.

As I understand it, most of the mass produced long arms are .250 wall chro-mo. If you want stronger, go with thicker walls or larger OD and the same wall thickness. I prefer the RE cartridge style joints over the Johnny Joints because of the threaded plate holding it all together rather than just a snap ring. PSC sells some bushings pre-mounted on a threaded stud that would work great on one end (cuts down on the noise and vibration transferred to the frame) with the RE style joints on the other end.

Out of curiosity, how many Johnny Joints have you seen with a blown out snap ring?

Out of curiosity, how many Johnny Joints have you seen with a blown out snap ring?

Thank you. If it works, what's the problem with it?

My JJ's are squeaky though, anyone know why? They are hard to get grease into. I bent a lower arm on the 'con this year, Currie tie rod too. Just slightly, but a little nonetheless.

bending happens, it's the breaking you gotta look out for. :D

Thank you. If it works, what's the problem with it?

My JJ's are squeaky though, anyone know why? They are hard to get grease into. I bent a lower arm on the 'con this year, Currie tie rod too. Just slightly, but a little nonetheless.

Yes, I know why they squeak and so do you. They have no grease in them. Figure out why and fix it.

Yes, I know why they squeak and so do you. They have no grease in them. Figure out why and fix it.

Any suggestions other than breaking them down? They are just tight enough that the rings won't go back on by hand, they need a press. I took one apart and had to take it down to Currie to have it put back together. They have some kind of press tool.
Thanks!

Out of curiosity, how many Johnny Joints have you seen with a blown out snap ring?

personally, none. Heard others in the group complain about their johnny joints failing, 2.

personally, none. Heard others in the group complain about their johnny joints failing, 2.


Were they actually Johnny Joints from Currie or any of the myriad of knock-offs out there?

The reason I ask is because I know for a fact that a 2.5" JJ installed correctly is capable of handling all of the side load duties required to locate an axle under a competition rig that is big, heavy, and rolled frequently without ever popping out the snap ring.

I also know why it can do it and others can't. John made the urethane races tight enough to have to be pressed into the barrel and done so with no grease makes it impossible for the snap ring to ever see any loads other than retaining the race. As it loads sideways the ball pushes into the urethane and swells it slightly against the barrel basically locking it in place and saving the snap ring.

Were they actually Johnny Joints from Currie or any of the myriad of knock-offs out there?

It is possible they were knock-offs, I never asked.

I have not been able to break mine up front upper arms, I am just looking for a strong flexable joint for building a set of arms around...