Fender Bolt Thingies

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OldSchool C-10

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Anyone know the proper name and a source for these? They are the ones under the front fenders, sort of a clip thing that hold the nut in a square hole.

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AuroraGirl

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Anyone know the proper name and a source for these? They are the ones under the front fenders, sort of a clip thing that hold the nut in a square hole.

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isnt that supposed to be a circle shape
 

AuroraGirl

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Also how many because I have a LOT of fender washers and bolts and nuts and metric/sae from cars... trucks.. gm from the era. no idea on which is which but i could always show some
 

OldSchool C-10

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isnt that supposed to be a circle shape
Don't think so, both were rusted bad enough that Blaster wouldn't help. Fenders are shot so I cut them out to keep from messing up the cab itself. This is picture of the square hole that this thing fits into and I think it has a sort of a spring attachment to hold it in the square hole.
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OldSchool C-10

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Are you sure that’s a clip? That looks like a nut that’s tack welded on place.
The other picture I just posted shows a clean hole, I didn't cut any welds. Once I cut the lower bolt in half the rest fell out onto the ground.
 

Laz_

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It’s called a u-nut. Lowes has them in the fastener section 5/16x18 I think. I used stainless bolts and washers with some anti seize to prevent galling.
 

WP29P4A

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We use those in audio/video racks, they are called captive nuts. They have several types and shapes of retainer to hold them in place.
 

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  • soundlab-m6-captive-nut-for-rack-fixing-pack-of-100-8155-p-3152873594.jpg
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AuroraGirl

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Don't think so, both were rusted bad enough that Blaster wouldn't help. Fenders are shot so I cut them out to keep from messing up the cab itself. This is picture of the square hole that this thing fits into and I think it has a sort of a spring attachment to hold it in the square hole.
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huh

Unique and learned something new
 

bucket

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That is a nut that is supposed to be pressed/welded into the fender. If you are replacing the fender, you don't need to worry about it as the fender will come with that weld nut installed already. The square hole in the cab is there for fender adjustment up/down, fore/aft.
 

WP29P4A

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It's basically a factory cheat, the floating nut held in place by the captive clip allows the factory worker to install the bolt without having to hold the nut in place. It also aids in alignment, because it floats.
 
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RecklessWOT

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Those are supposed to be welded on as far as I know. You didn't cut the weld because it looks like rust took care of that part for you. Not like it's a heavy weld, they're basically just tacked in. A little bit of rust will easily make that weld disappear, or at least compromise it enough to crack easily when just a little bit of torque is applied. The rust that forms in the threads is usually stronger than that little tack so the whole thing just snaps off and spins when you try to loosen it. That's not just a squarebody thing, that's uses on everything from fenders on our trucks to the subframes of little foreign economy cars and everything inbetween.
 

WP29P4A

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Here is a better pic of the different types of clip, captive nuts.
 

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  • Screenshot 2022-05-12 at 14-19-11 McMaster-Carr.png
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