72 GMC 4x4 Build

[CUSTOM/10]

Brian;

Once you get the 70 frame back from being straightened out put the frames side by side and look them over for any differences. There shouldn’t be much.
I believe the forward "rear spring mounts" are a bit different. Taller I believe on the 72. Either frame may or may not have a steering box reinforcement plate on the inside of the frame rail. And of course the vin number stamped in the frame. But from what I have heard some GMC frames didn't have any vin numbers on the frame.

Oh, either frame may or may not have a spring retainer on the driver’s side front spring. This consists of an angle plate bolted to the frame behind the spring and a plate welded across the front mount. these will keep the spring somewhat in place if it breaks !

I myself, if your original frame can be straightened correctly, would use it just to keep the frame & vin tag matching. Just my 2 cents !

Gary

[bhammer]

Yea, I would prefer to use the original one with my truck. I looked all over on the 70 frame for a stamp but didn't find anything in the normal spots, (near steering box and between cab mounts) but it is pretty caked with road grime so maybe when I get it blasted I will be able to find it. The original GMC frame has a stamp in it. They appear to be pretty much the same. Neither frame has a plate behind the steering box, I am going to put one in on both to give them some strength. y dad is trying to talk me into boxing the frame but I don't know if I want to put all that money and time into it. I'll know more once I get them both straight and side by side. Thanks for the feedback.

Brian

[dbash]

Originally Posted by bhammer

Yea, I would prefer to use the original one with my truck. I looked all over on the 70 frame for a stamp but didn't find anything in the normal spots, (near steering box and between cab mounts) but it is pretty caked with road grime so maybe when I get it blasted I will be able to find it. The original GMC frame has a stamp in it. They appear to be pretty much the same. Neither frame has a plate behind the steering box, I am going to put one in on both to give them some strength. y dad is trying to talk me into boxing the frame but I don't know if I want to put all that money and time into it. I'll know more once I get them both straight and side by side. Thanks for the feedback.

Brian

You seem to know your stuff, my 2 cents.... I would not box the frame until you are happy with how your motor and headers are positioned. Gets tight in these frames if you upgrade the motor.

Looking forward to your build.

[bhammer]

Allright, got my replacement frame back from the media blaster and she looks good. Definitely needs some TLC to get her back into good shape, a little cutting, grinding, etc. Once I got it blasted though I was looking for some identifying numbers on the frame so I can tell what I have. All I can find was the number in the picture on the side of the frame rail and theres a different number on the passenger side as well. Anyone know what this number means? There are no other numbers stamped into the frame anywhere else on the frame. Also can someone tell me what the bracket behind the front leaf, rear shackle on the drivers side is for? Never seen that. I think the frame is from a 70, or at least thats what I was told. Hoping someone can shed some light on this for me. Thanks in advance.....

[CUSTOM/10]

Tha bracket is to keep the spring from shifting backwards if the front spring or spring bolt breaks. There should also be a plate welded across the front spring mount to keep it from going forward.

Was this new frame from a GMC, I've heard that some of the GMC frames didn't have the vin numbers stamped in them.

If it has vin numbers, they would be on the top of the drivers side frame rail, near the steering box, and about were the drivers side door would be.

Gary