GM Axle Questions

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Radiohead

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As far as I know, no factory axles had closed spring perches. They are open at each end.

Your axle has closed perches. I'm not for sure on the gmt 400's I'd have to look at mine.
I double checked the picture I took of the supposedly stock axle I'm swapping and I blew up the image for this screen shot. I wonder what that means. Of course I haven't gone outside yet to get a better look at the rear side.
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PrairieDrifter

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I double checked the picture I took of the supposedly stock axle I'm swapping and I blew up the image for this screen shot. I wonder what that means. Of course I haven't gone outside yet to get a better look at the rear side.
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I'm not 100%. A Dana 70 could have I suppose.

That weld on front looks a little suspicious from the picture.
 

bucket

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As far as I know, no factory axles had closed spring perches. They are open at each end.

Your axle has closed perches. I'm not for sure on the gmt 400's I'd have to look at mine.

All 14FF's prior to '84 had cast perches, far as I know.

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My '79 Dana 70 has cast perches as well. I don't know if they got the stamped steel perches later.

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Here's a factory perch on a 6-lug 4x4 14SF axle, although I have relocated them.

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^^^Note the stamped perches. If the 14SF ever got cast perches from the factory, I would be shocked. I don't recall seeing one with anything other than stamped perches. The axle in the picture is a '90 unit, iirc.
 

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I'm not 100%. A Dana 70 could have I suppose.

That weld on front looks a little suspicious from the picture.
I think what looks like a sus weld is actually skudge from where the swaybar U bolts lived. I saw that too and went eww. I hadn't considered the perch to be cast, but the one wanting to be the replacement housing from a '77 suburban looks like cast perches too. I'll get better pics later on and do an edit.

Edit - no fresh pics, but yes they're cast perches. I imagine those would be a pita to move compared to the newer style. Hadn't considered perch style before...
Zoom in on the '77 housing
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bucket

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I think what looks like a sus weld is actually skudge from where the swaybar U bolts lived. I saw that too and went eww. I hadn't considered the perch to be cast, but the one wanting to be the replacement housing from a '77 suburban looks like cast perches too. I'll get better pics later on and do an edit.

Edit - no fresh pics, but yes they're cast perches. I imagine those would be a pita to move compared to the newer style. Hadn't considered perch style before...
Zoom in on the '77 housing
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Factory welds were often very ugly. I've seen perch welds and subrame/frame welds (on the GM cars) that look like GM hired Ray Charles to work at the factory.

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