• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Upper and Lower Control Arm build Jeepspeed Style...

crazyjim

NAXJA Forum User
Location
SoCal
Figured I'd post these over here, as this is something both Jeepspeeders and Rock Crawlers alike can appreciate. Built some UCA and LCA's this weekend for the Jeep. I run short arms on drop brackets, they do really well. You can follow my build here:

http://www.naxja.org/forum/showthread.php?t=983758

Head to the later pages to see the forward progress made lately. Anywho, the lowers are .250 wall 4130 with 1.25" Chromo heims. The uppers are 1.5" .120 wall sleeved with 1.75" .120 wall DOM with 7/8" heims on one end, and 1/4" stainless plate for the axle end. The axle end of the lowers aren't finished yet, still need to drill a hole and round the ends down, but you get the point.

LCA2.jpg


LCA3.jpg


IMG_1457.jpg


IMG_1465.jpg


IMG_1471.jpg


IMG_1466.jpg


IMG_1489.jpg


IMG_1494.jpg


IMG_1492.jpg
 
Very nice work :thumbup:
 
nice work. I know you have a pretty custom d30 up front but ya worried about the lower arms hitting anything at full droop? on a stockish setup a perfectly straight arm hits the shock mount. only reason i'm askin'
 
i would think that the way the heims mount, the skinnier part with the threads is right where stock arms would hit, so it probably will allow for a little more droop, and like he said, he's running drop brackets.
speaking of drop brackets, Jim, i've seen issues with drop brackets coming loose at the bolt mounting points, and sometimes even ripping the mounts entirely off the jeep. this has been without the bracing that most of them come with now, and in rock crawling applications. what do you have setup to be beef?
 
Very nice work :thumbup:

Thank you, welding credit goes to my buddy though.

nice work. I know you have a pretty custom d30 up front but ya worried about the lower arms hitting anything at full droop? on a stockish setup a perfectly straight arm hits the shock mount. only reason i'm askin'

Well, I've got my shock mounts relocated lower to the side of the LCA bracket. Boxed the LCA bracket in and cut the front half of the piece that hits off. You can see it here:

DSCF3247.jpg


It really isn't all that much work, and allows for a longer shock.

i would think that the way the heims mount, the skinnier part with the threads is right where stock arms would hit, so it probably will allow for a little more droop, and like he said, he's running drop brackets.
speaking of drop brackets, Jim, i've seen issues with drop brackets coming loose at the bolt mounting points, and sometimes even ripping the mounts entirely off the jeep. this has been without the bracing that most of them come with now, and in rock crawling applications. what do you have setup to be beef?

I've got RC drop brackets, and I've heard of the same issues. I stitch welded them on to prevent these problems. There's a 1" or so weld on both side connecting to the bracket to the brace, and a few 1" welds connecting the brace to the frame.
 
Good Lawd Jim! :D
 
My only critique is more of a question, really:
Would rubber bushings (OE style) help preserve weld integrity via less vibration, or is this benefit outweighed by the strength advantage of heims?
I haven't heard of sudden catastrophic bushing failure, is why I ask.
 
First of all, thanks everybody! I put a lot of thought into these, and wanted them to hold up. Only time will tell :D


My only critique is more of a question, really:
Would rubber bushings (OE style) help preserve weld integrity via less vibration, or is this benefit outweighed by the strength advantage of heims?
I haven't heard of sudden catastrophic bushing failure, is why I ask.

What weld do you see failing? The welds on the control arms? If so I can 100% guarantee you they will not fail. Those are some HIGH heat nicely penetrating welds. As for heims vs. bushings, in what application have you seen a heim have a "catastrophic failure" that a bushing would have survived? I'd definitely place more trust in a chromolly heim than I would a bushing, rubber or poly.

On the opposite side of things, a heim WILL need more maintenance, and will requite frequent checks for play and wear with the abuse I plan on putting these through, but the advantages far outweigh the disadvantages. It's not only a strength advantage, but the advantage of having a TIGHT well performing suspension. Same reason I have 3 different kinds of stiffeners on the Jeep plus a cage, it rids the Jeep of the "flex and twist" they so commonly have. Doing the TNT , TMR, and T&J stiffeners all together, gave me another few MPH in the rough stuff for sure.

The only weak point now IMO is going to be the control arm mounts, axle side. My drop brackets are welded, and are beef, so I'm not concerned about those. I'll also still be running a bushing in the UCA mount on the axle end, this will reduce some of the shock the heims would otherwise see. I've also been eyeballing Curries Johnny Joint kit they sell, but worry it might be a bit too stiff. All in all only time will tell, but if I had to guess, if anything will fail it will be the control arm mounts. When / if they do, expect another fab thread like this one beefing them up ;)

I guess I gotta ask since no one else is. Whats the microwave for? He making pizzas in the Garage?

I WISH we could run arms like that in Jeepspeed!

M R Purdy.

EDIT - Just noticed that you had your lower shock bolt going the correct way. Nice!

Haha thanks dude, I'm not sure what's involved with becoming an "off the shelf" part but it may be something we look into.
 
just another thought.

ya think the 2 stock uca bushings will be able to compensate for the binding in a 4 link w/ panhard suspension?

will probably be fine as they don't nearly as much as a radius arm style suspension that utilize only those 2 rubber bushings as well. but bending/breaking of axle mounts is a pretty common occurence with those...


just thinkin out loud!
 
First of all, thanks everybody! I put a lot of thought into these, and wanted them to hold up. Only time will tell :D




What weld do you see failing? The welds on the control arms? If so I can 100% guarantee you they will not fail. Those are some HIGH heat nicely penetrating welds. As for heims vs. bushings, in what application have you seen a heim have a "catastrophic failure" that a bushing would have survived? I'd definitely place more trust in a chromolly heim than I would a bushing, rubber or poly.

On the opposite side of things, a heim WILL need more maintenance, and will requite frequent checks for play and wear with the abuse I plan on putting these through, but the advantages far outweigh the disadvantages. It's not only a strength advantage, but the advantage of having a TIGHT well performing suspension. Same reason I have 3 different kinds of stiffeners on the Jeep plus a cage, it rids the Jeep of the "flex and twist" they so commonly have. Doing the TNT , TMR, and T&J stiffeners all together, gave me another few MPH in the rough stuff for sure.

The only weak point now IMO is going to be the control arm mounts, axle side. My drop brackets are welded, and are beef, so I'm not concerned about those. I'll also still be running a bushing in the UCA mount on the axle end, this will reduce some of the shock the heims would otherwise see. I've also been eyeballing Curries Johnny Joint kit they sell, but worry it might be a bit too stiff. All in all only time will tell, but if I had to guess, if anything will fail it will be the control arm mounts. When / if they do, expect another fab thread like this one beefing them up ;)
.

Thanks for the education!
 
first off great build! been watching your other thread. i love heims, id take them over any other joint any time, they just work.
i agree heims usually dont fail, but when they seize up, its horrible. below you can see whats left of a heim. was in my RE trac bar. the heim was bad so i went to swap it out but the threads were seized. ended up torching it A LOT and still woulnt budge, we pried on it so intensely it broke the heim!!! ya. that seized.

7b582b5e.jpg



sowith that said. as much i love heims and them never failing, may not be a bad idea to build a few spares...just in case...
 
Heims are great but they need to be constantly maintained and replaced when worn. The heim in the pic was shot a year before it failed, wholly crap.
 
Back
Top