Frame/chassis problem- crack in fender well

weeeee

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Wondering what could have caused this. Some signs of the UCA impacting the upper shock tower, but I don't think any type of impact (at least not from the UCA) would have caused this crack in the fender well metal.

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Towards to front of the UCA (left), can see some small gouging where it has been contacting the upper shock tower.

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Damn. That gap between the bushing and washer in your fist pic looks a little big as well.

Caught that too. It was torqued per the FSM spec but I guess it loosened up.

I'll likely re-weld the fender metal before the crack expands but I figured I'd see if anyone else has been having the same issue.
 
This was a problem with the FJ cruiser but was supposed to be taken care of on the 150 chassis. It comes down to, these frames flex quite a bit under hard use, which stresses the body.
 
Do you have a larger, aftermarket battery?

Odyssey 31M where the stock battery used to be. Crack is also on the driver's side (under the battery tray). Are you thinking the added stress could start cracking the metal underneath?

This was a problem with the FJ cruiser but was supposed to be taken care of on the 150 chassis. It comes down to, these frames flex quite a bit under hard use, which stresses the body.

Interesting. I'll need to look into this. Was there a self-fix? I might try re-welding the area before it spreads. I'd consider the truck getting some pretty moderate to heavy usage on trails etc. but only occasional wheeling. Issue didn't manifest until the Kings/TC UCAs were installed and a recent trip.
 
Thanks for the lead [MENTION=32290]gm350reratliff[/MENTION]

Looks like this problem was definitely on some of the FJC/Prados before

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DSC_0254.jpg~original
 
Odyssey 31M where the stock battery used to be. Crack is also on the driver's side (under the battery tray). Are you thinking the added stress could start cracking the metal underneath?
Yes. As the crack gets worse another will develop in the sheet metal below the left headlight, at which time you can move the (tied down) battery easily with your hands and see exactly the flexing that causes the cracks. Mine started about 3 years ago and looked exactly like yours within 6 months of installing a 31M battery.

I welded mine a few times but it always broke again. I now have a couple 1/8" steel plates on each side of the cracks bolted together through the sheet metal, which seems to be holding. I plan to fabricate some kind of a strut from the radiator mount to further back on the fender or to the firewall, connecting to the top of the battery hold down to redistribute some of the load.
 
Yes. As the crack gets worse another will develop in the sheet metal below the left headlight, at which time you can move the (tied down) battery easily with your hands and see exactly the flexing that causes the cracks. Mine started about 3 years ago and looked exactly like yours within 6 months of installing a 31M battery.

I welded mine a few times but it always broke again. I now have a couple 1/8" steel plates on each side of the cracks bolted together through the sheet metal, which seems to be holding. I plan to fabricate some kind of a strut from the radiator mount to further back on the fender or to the firewall, connecting to the top of the battery hold down to redistribute some of the load.

Interesting. So a couple possible scenarios here. I might do the reinforcement when I'm in there welding it back up. Would you happen to have any photos?
 
Also, as far as the UCA nut/bolt loosening, I recommend a lock nut to prevent it. If you have been driving for a while with it loose, it will damage the UCA bushings, BTDT.
 
Interesting. So a couple possible scenarios here. I might do the reinforcement when I'm in there welding it back up. Would you happen to have any photos?
I just took some, excuse the mud

Here's where the second crack develops
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Mended fender crack and the lock nut. I also reversed the UCA bolts so they can be removed from the rear and not have to mess with the battery or A/C lines to remove the UCAs.
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Before you weld those cracks, drill a 3/16 hole where the crack ends to relieve some of the stress in the metal. It'll help prevent it from cracking in the same spot again.
 
First, I'd stop drill that crack to prevent further migration. Then bolt or rivet a doubler on either side.
 
I know in the case of the FJs there was supposedly one or two guy who swore up and down to their mothers that they never off-roaded or modded the truck and still got this crack. But it seemed like a lot of them might have been more from jumping/hitting on the ground hard. How much "hardcore" wheeling like that are you guys doing? Just curious, not saying that's the cause (I'm more interested in the correlation as I haven't seen many 4th or 5th gens exhibit this).
[MENTION=44305]weeeee[/MENTION] [MENTION=78273]Jeremy556[/MENTION]

Post Note-

You guys were making me paranoid, had to go check my 4Runner to see if there were any signs of cracking since I'm not kind to here on the trails. I don't see any so far.
 
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sucks to see this on the 150 platform. i'm familiar with the issue on the FJ, but had never heard a heavier battery cited as a contributor to the problem... is this the case?

seconding [MENTION=78273]Jeremy556[/MENTION] recommending a lock nut for the UCA bolt. that gap is not cool. a thin jam nut will do the trick.
 
Mine has had a rough life for sure.

I have never heard anyone else blame it on the battery, and I have only come to that conclusion in the last few months
 
Sooo...after relieving the stress crack and re-welding it again, the split occurred in two different areas this time. I really think what [MENTION=78273]Jeremy556[/MENTION] is on to something. I haven't heard of it occurring to anyone else just yet. Pretty sure the sheet metal in that location is not strong enough to withstand the additional battery weight and the abuse off road.

Looks like I'll be swapping to a couple smaller 35Ms.
 
Sooo...after relieving the stress crack and re-welding it again, the split occurred in two different areas this time. I really think what [MENTION=78273]Jeremy556[/MENTION] is on to something. I haven't heard of it occurring to anyone else just yet. Pretty sure the sheet metal in that location is not strong enough to withstand the additional battery weight and the abuse off road.

Looks like I'll be swapping to a couple smaller 35Ms.

thanks for the update [MENTION=44305]weeeee[/MENTION] Sorry it didn't end there.
I remember when this thread came out. It was a good observation by Jeremy556
This is definitely something to keep in mind. That battery swap is pretty common.
 
I'm really not sure what's causing these cracks, we jumped the truck 3 times in Baja, and I have the Odyssey group 31, in a pelfrey cage, and no cracks yet.

Either I'm lucky, or it'll finally crack when I go over a speed bump or something stupid.
 

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