Cracked lower control arm mount

Justin Homan

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This morning i noticed a cracked lca mount on the axle side of my Jeep. Its not an ideal time for this issue as i need to drive it 45 minutes away from home tomorrow and i dont have the time or parts to fix it till Thursday next week. The crack is a fairly small one but i am worried about it as i like my Jeep to be mechanically perfect. Also i know my current style control arms can/will cause this issue and will be changing them to currie/metalcloak as money allows. Do yall think ill be safe driving kn these till Thursday? Also any recommendations for new, heavy duty mounts?
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i'd have that re-welded to the axle, if it's going to be driven b4 upgraded brackets are ordered.
but honestly i see no evidence of a recent break, those cracks look like they've been there open for awhile to me. i see no clean metal indicating it was very recent.
 
I Agree, it looks like it’s been like that for a while. Is it just one or both? Take it to a muffler shop and have them weld it up if you don’t have a welder.
 
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i'd have that re-welded to the axle, if it's going to be driven b4 upgraded brackets are ordered.
but honestly i see no evidence of a recent break, those cracks look like they've been there open for awhile to me. i see no clean metal indicating it was very recent.
I hadnt even thought it could be old. Jeep still drives fine so ill make the trip tomorrow and fix it as soon as i get the chance.
 
I Agree, it looks like it’s been like that for a while. Is it just one or both? Take it to a muffler shop and have them weld it up if you don’t have a welder.
I wish i would have noticed yesterday! Already had the jeep at an exhaust shop to rework the tailpipe. Luckily i have a welder at home so ill weld it up later this week and order new brackets after my vacation.
 
I Agree, it looks like it’s been like that for a while. Is it just one or both? Take it to a muffler shop and have them weld it up if you don’t have a welder.

And bring a 20 dollar bill. Stop at an independent shop that doesn't appear to have many cars in the parking lot. I had a brace welded to another car project like that (off the books) before I had a welder
 
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I wish i would have noticed yesterday! Already had the jeep at an exhaust shop to rework the tailpipe. Luckily i have a welder at home so ill weld it up later this week and order new brackets after my vacation.
Is your welder big enough for that job? I wouldn't try to use a 110v welder, that's a lot of steel there to sink the heat away from the puddle.
 
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Is your welder big enough for that job? I wouldn't try to use a 110v welder, that's a lot of steel there to sink the heat away from the puddle.

I agree. It could be done properly with a 110v machine in a pinch... if the axle were removed from the vehicle, then taken apart and the area was cleaned and excavated for additional penetration. Preheat would also be beneficial, but that's a lot of work
 
If possible try and stop-drill both sides of the crack. That should help it from spreading farther. And when you get it welded back up have them stop-drill it before welding if you didn't get it done. That will help relieve any stress and make for a stronger repair and less likely for it to want to crack the new repair weld.
 
Incidentally, cracked control arm welds like happened to you are commonly caused by inexpensive control arms with bushings at each end which restricts how well they flex. I can only see one end of your control arms but if both ends are like that you can expect more cracks in the future if you wheel on trails that are uneven enough to push the suspension/flex it really hard. At a minimum a control arm should have a flex joint at at least one end. An inflexible control arm places extra stress on their mounts which can cause their welds to crack or even tear the mount completely away from what it's welded to as happened to me

I had Tera's 1st generation arms many years ago with rubber bushings at both ends and they tore two control arm mounts off where they were welded.
 
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If possible try and stop-drill both sides of the crack. That should help it from spreading farther. And when you get it welded back up have them stop-drill it before welding if you didn't get it done. That will help relieve any stress and make for a stronger repair and less likely for it to want to crack the new repair weld.
Definitely gonna give that a try and see how it holds up. Probably gonna change to thicker brackets eventually but at least to get me bye.
 
Incidentally, cracked control arm welds like happened to you are commonly caused by inexpensive control arms with bushings at each end. I can only see one end of your control arms but if both ends are like that you can expect more cracks in the future if you wheel on trails that are uneven enough to push the suspension/flex it really hard. At a minimum a control arm should have a flex joint at at least one end.

I had Tera's 1st generation arms many years ago with rubber bushings at both ends and they tore two control arms off where they were welded.
They do have a heim joint on one end although i do want to change them to currie/metalcloak/savvy when i have the money for it.
 
A TJ Front control arm mount is only welded externally...drop the arm and weld inside and out for greater strength.
Thank for the tip, ive been wanting to drop thr jeep about 1.5 inches and will need to remove it to adjust the control arms. Looks like I've got a nice project for this weekend!
 
I don’t think there’s any steel on a TJ that can’t be welded with a decent quality 110v welder. Most are rated for ay least 5/16” think steel
Only in ideal conditions with small pieces. Think surface area like big pieces or small pieces being welded to big pieces. My 3/16" tcase skidplate sucked (sinked) most of the heat away from the transmission mount I was trying to weld to it with my 110v 140 amp Hobart MIG welder. That's why I sold it and bought my current 180 amp 220v Miller.