Front Control Arm Bracket Breakage and Repair (1 Viewer)

[OGBeno]

Hey there folks:

After a rough spring and summer of off-roading, I noticed that my front control arm brackets on the axle housing were cracking. This was only occurring on the USPS and in the same area on both sides of the bracket that surrounds the front control arm.

I have the stock arms with Slee blues and this combination also afflicted Inverness on the Rubicon. His was much worse in that the actual bracketry tore off of the axle housing on the USPS. It was welded on the trail and later Inverness used some bar stock to reinforce the bracketry.

It seems that the Slee blues are especially hard and do not have as much axial movement side to side. As such, the stress and pressure of articulation is transferred to the bracketry.

Mine were not as bad as Inverness's were--but bad enough that the cracks reached from the bottom of the bracket all the way up to the axle housing and would have eventually broken off.

I went up to Alia176's shop today and welded the cracks and then added an 8"x1" metal bar on each side to buttress the stress of articulation.

I would recommend other 80 series owners with the stiffer Slee blue bushings to check their USPS brackets as well for signs of cracking.

Here are some before and after pics.

Best.
-onur

1st picture shows the crack and it was the same on the opposite side as well.

2nd picture shows the bar stock welded onto the bracket as well as a weld on the crack.

3rd pic is of the front control arm back in place.

 

[Wrench]

WOW! Not good! I have yellows. But will check anyways.

 

[sleeoffroad]

The cracking of the axle side brackets were a common thing in Australia when lcool started years ago and people reported on it. We did not see it in the US to nearly the same extend as they saw it. I guess we have finally caught up. Bushings might play a small part, but I think it is mostly the trucks just getting old and worked hard. Good for anyone to check.

 

[OGBeno]

The cracking of the axle side brackets were a common thing in Australia when lcool started years ago and people reported on it. We did not see it in the US to nearly the same extend as they saw it. I guess we have finally caught up. Bushings might play a small part, but I think it is mostly the trucks just getting old and worked hard. Good for anyone to check.

Good info. Christo.

Thanks!

 

[retrofive]

Had to go check mine for fun. Im good.... for now

 

[IBCRUSN]

Thanks for the heads up! I better check this out pretty quick since my has been flogged this year as well.

 

[alia176]

I agree with Christo, age and lots of twisting of the front suspension is probably the root cause. I know of a third vehicle with oem bushings that experienced the same thing.

Beno's camera pics aren't the greatest so it's hard to see much of anything. However, the actual "crack" is vertical and not too far from the rear bolt holes. The actual weld between the bracket and the axle housing appeared intact and there was NO gear oil seeping out.

I wonder if the Slee caster plates actually help with this symptom somewhat by not allowing the axle bracket to get stressed as much. All the stress might be translated to the welded area instead, but I dunno for sure.

Beno, can you orient the first two pics properly so they're easier to understand for most folks?

Thanks.

 

[450 DUDE]

Thanks for the heads up!.....



BTW someone get Beno a camera

ken

 

[80t0ylc]

X2 on thanks for the heads up! Two things I hadn't noticed before:

1. The sway bar on my '94 is attached to rear of LCA brackets. This has got to contribute to stress during heavy articulation. I think I'll be discoing sway bar in the future before running some trails.

2. LCA brackets are spot welded to axle at ends( they have solid bead in middle, under axle). Is this to allow for flex or to save money during manufacturing?

One other point, in another thread I remember Kevin (Tools R Us) talking about the importance of having a limited amount of torsional movement for the arms inside LCA brackets to aid in flex ability of the front axle. Short of having a narrower arm (which I think Kevin tried), what else could be done? It would be nice if you could widen the ends of the bracket.

 

[TrickyT]

Good catch, beno! Because you caught it early, this was a much easier repair than what Inverness had to deal with.

...Bushings might play a small part, but I think it is mostly the trucks just getting old and worked hard...

I will testify that beno works his truck hard!

 

[landtank]

that sucks. Would you know how the bushings were pressed in on both trucks? Mainly concerned if both used my template.

Also, anyone with plates could sticth a few small welds along the bottom of the braket to help support the bracket.

 

[OGBeno]

that sucks. Would you know how the bushings were pressed in on both trucks? Mainly concerned if both used my template.

Also, anyone with plates could sticth a few small welds along the bottom of the braket to help support the bracket.

Yes, I used your template to install the bushings Rick.

Some small stitch welds might not be a bad idea for reinforcement sake.

 

[Tools R Us]

On lifted rigs, when the front axle is flexed, the flex is limited by the arms hitting the brackets. The arm tries to move at an angle compared to the brackets, will hit one side at the front and the other at the rear. Each time it's flexed hard the brackets are bent/flexed, with repeated flexing this is going to crack the metal like happened in this case.

The first pic is from the front, second from the rear. I should have held a straight edge on the bracket, it's flexed out at the bottom, but is hard to see in the pic. These are forklift flex pix, on the trail it can be force flexed farther, flexing the bracket more. The third pic is my arm, one of the changes was narrower bushings, they no longer hit, flex more and easier.

 

[Tools R Us]

I narrowed the stock bushings about .3" and made the new arms the same width. Have never tried, but grinding the top of the front bushing holder area of the stock arm, somewhat like the red line, may reduce the stress on the brackets and improve axle flex?

 

[OGBeno]

Kevin:

Can you speak more about the arms that you made? I think you have documented it in another thread, but if it is relevant to easing the stress on the control arm brackets, it would be legitimate here.

Also, interestingly, the brackets on either side of the rig (USDS/ USPS) are different. The USPS has a half moon cut out of the bracket on the bottom side near the rear bushing. The USDS does not have a half moon cut out and is solid metal. Interesting difference and not really sure one side is different than the other.

 

[Riad]

Dag Onur. You even managed to dent your front Panhard rod bracket. I say get a diamond axle housing and call it a day.

EDIT: Never mind; I was looking at Tool's pictures and thought that's your axle.

 

[Tools R Us]

Kevin:

Can you speak more about the arms that you made? I think you have documented it in another thread, but if it is relevant to easing the stress on the control arm brackets, it would be legitimate here.
...

The arm thread; https://forum.ih8mud.com/80-series-tech/94176-my-new-front-arms.html

 

[Tools R Us]

Dag Onur. You even managed to dent your front Panhard rod bracket. I say get a diamond axle housing and call it a day.

EDIT: Never mind; I was looking at Tool's pictures and thought that's your axle.

If your going to play in the rocks, stuff is going to get bent. Have only hit the panhard bracket a few times and bent it once. If it becomes a bigger problem will add a skid/gusset. Don't see how a Diamond would help, not bending the housing? To install a Diamond would need to ether cut off the stock brackets and weld to it or make new ones. In this case it would be much easier to beef up the stock bracket?

 

[DMOZ]

While looking for a way to reduce the front end bind, as well as a way to correct for caster, i came across these radius arms from Superior Engineering in Oz. Curious if anybody has any experience with these?

Superior Engineering

They are available for 3", 4", and 5" lifts...

 

[Tapage]

Something like only use 3 bolts on your stock control arms ..

make sense ..