Bolt patterns for 65-75 chevy truck frames

[MercadesCage]

Thanks

[57larry]

it would be easier to use the respective frame and upgrade the suspension to 5 lugs

[Captainfab]

The '63-'66 body's can be mounted onto the '67-'72 frames with minimal changes. The rear cab mount on the '67-'72 frames are a little different, the radiator crossmember utilized in the '63-'66's is not there on the '67-'72, and the front frame horns for the bumper are different. Scoti may know if other issues.

[SCOTI]

I agree w/the suggestion of swapping the later suspension & discs to earlier frame if @ all possible. Much easier in my honest opinion....

If that's not an option, the 63-72 frames are similar enough that the swap is fairly easy. As mentioned the rear cab mounts need spacers or to be raised (1" if I remember correctly). The radiator core support needs to be moved forward slightly & up (or use spacers again). A new radiator mount will need to be fabbed. The front frame horns won't allow a bolt-on swap for the bumper (I made brackets from another set of frame horns & steel plate so the bumper could be adjusted if needed). The bed is pretty much a direct swap.

The 73-up frame could also prob be used but again the mounts would require tweaking (even more vs. a 67-72 frame). I have not personally done this swap so I can't offer specifics.

[gkesseru]

I have just moved the entire front suspension from an 81 Step to a 68 and have both frames to compare. No problem except for some drilling and hole widening. The 68 frame is 1/4 inches wider in the front, but a 5 pound hammer "eased" it into place. Having a couple long tapered punches really helped align the holes. As far as swapping cabs, that would be really hard, since the earlier frame has a lowered section where the cab sits. On the 67-72 frame, the cab part of the frame sits about 3 inches lower than the bed part of the frame. Also the later cab mounts are inboard to make room for the externally mounted gas tank. The 73-on frames are level in the middle so the older cab and bed won't align on the newer frames. You can swap a 4X4 by moving cab mounts, since putting 3 inch risers won't look too bad on a 4X4.