67-8 vs 69-72 core support frame horn

[BrianG]

I am having some issues with the alignment of my front sheet metal. Particularly, it seems as though the core support is too high compared to the front of the cab. If the core support would go down a little then the alignment would be going much better.

So, while researching this, I have stumbled across a topic that seems to be truly unanswered or unproven. Some say that the frame horns that support the core support sit lower than the top of the frame on some years, and flush with the top of the frame on other years. I know that some (I believe 67-68) have a smaller hole in them also.

My frame horns are flush with the top of the frame. The mounts I have are approximately an inch thick, so the core support sits above the top of the frame by that inch. Is this normal? What would it hurt to take it down some? If I were to take it closer to the frame would that mean that my bumper will not line up with the grille correctly?

Can anyone provide proof that the height of the core support horn was ever not flush with the top of the frame. I don't need proof that it was flush, I have one that is.

Thanks for the help.

[68bowtie]

my 68 c20 horns sit flush with the frame. the washer/bushing between the support and horn is no where close to 1 inch...

[Boog]

The problem most likely is not with your core support mounts or cushions. Look at the cab mounts and cushions. They may be deteriorated enough to cause the cab to be too low to line up the fender.
If I'm not mistaken there are a couple different height cab mounts also. Maybe one for 2wd and one for 4wd trucks. Someone can confirm that?
Some pictures always help in these situations. We don't know if you are only replacing the front clip or doing a complete body off rebuild so particulars are important too.

[BrianG]

It is at the end of a complete frame off rebuild. Or maybe I should say BUILD without the RE because it has many new parts or used parts from other vehicles. The cab mounts are new. I am having the same issue that I've seen posted here before, but I'm not really sure how each of those situations were resolved. The body line from the tailgate end of the bed all the way to the grille end of the door is straight. With the core support mounts that I have (69-72 style) the front appears to be too high. This caused the seam between the fender and door to not align well. Too close at the top and too far away at the bottom.

Again, is there any proof that the core support frame horns, mounts, perches, whatever they are called were ever not flush with the top of the frame. Looking through some pictures on this site, I have seen some core support pictures that appear to sit at least a half inch, to possibly almost an inch above the to of the frame. Is this normal.

What does not make sense to me is that if the 67-68 core support used a very thin spacer, then it would sit lower to the frame. The cab mounts are the same, so how is this resolved? Bottom line is, if I can lower my core support closer to the frame, it is going to help in the alignment of the fender to the door and help keep the body line straight. However, what other issues might I have if I do so? Will my bumper then not fit right to the grille? could I have other issues with the radiator or anything else?

[BrianG]

Originally Posted by 68bowtie

my 68 c20 horns sit flush with the frame. the washer/bushing between the support and horn is no where close to 1 inch...

Interesting... Do you or anyone else have any pictures of the distance between the bottom of the core support and the frame? Pictures from all years welcome. This may help answer if there are truly differences between the years.

[FirstOwner69]

What year is your truck? 1/2 or 3/4 ton? Sounds like it's probably a 69-72, but I'm not sure.

[BrianG]

Originally Posted by FirstOwner69

What year is your truck? 1/2 or 3/4 ton? Sounds like it's probably a 69-72, but I'm not sure.

Well, it will be a 69 4x4, but like I said, it is made up of various parts from various years.

1/2 ton 4x4 that is

[FirstOwner69]

Originally Posted by BrianG

Well, it will be a 69 4x4, but like I said, it is made up of various parts from various years.

1/2 ton 4x4 that is

Is the frame from a 2WD 1/2 ton, 4WD 1/2 ton, or some other combination? Also, what year is the frame?

[hugger6933]

If the core support is too high at the top the gap in the fenders is gonna be tight at the doors at the top and wide at the bottom. Of course it sounds like you have learned this on your own. From what I have determined the difference in the years model difference on the front body bushing is the size of the hole diameter and not the thickness. Where there are a difference in the thickness of the bushing is in the model of the truck. Now some may need to chime in here as I have not mapped this all the way out as yet but the C30 bushings are most def different than the ones for the C-10's. And the C and K series seem to be different so this is where some of the difference might come in.
Now what I would do is to hang the front bumper to see if the front is too high or the cab is too low.
Yes and I drum this into my dad's head every time he wants to try to "make "something fit you can't move one parts problem with out moving the problem farther down the line, and if you keep going by the time you get to the bumper you are liable to have a huge honking mess on your hands trying to line anything to anywhere near close.
So if the bumper doesn't look right when you sit it up on the brackets get some core support mounts that are one inch thinner than the ones you have now and you'll be good to go. If that makes any sense,and your frame isn't tweaked a little but I don't want to freak you out or panic you it sounds just like it is as simple as the wrong rubbers on the core support mounts.
Normally the frame horns are typically referred to as the forward part from the forward most cross member. Good luck and happy sanding. Jim

[hugger6933]

Sorry I usually reserve that tag line for the paint and body section. Jim

[BrianG]

Originally Posted by FirstOwner69

Is the frame from a 2WD 1/2 ton, 4WD 1/2 ton, or some other combination? Also, what year is the frame?

Funny! I just sent you a PM actually. I didn't see that you had replied, but did find a post where you also had some issues. It is a 69 1/2 ton 4x4. But it is definitely a Frankenstein truck. I believe the frame is 69 or later because it has the larger holes for the core support mounts.

I think at this point, I'm not really looking for what 'should' be there as much as will the 67-68 mounts work without other issues such as the bumper. Will the 67-68 core support mounts actually lower the core support closer to the frame, and will this be an issue.

I see you ended up using 67-68 core support mounts. How did this end up working for you? Any issue that you can share with the installation, or have you had any issues since? Did it help correct the alignment between the fenders and the cab? Thanks!

[BrianG]

Originally Posted by hugger6933

If the core support is too high at the top the gap in the fenders is gonna be tight at the doors at the top and wide at the bottom. Of course it sounds like you have learned this on your own. From what I have determined the difference in the years model difference on the front body bushing is the size of the hole diameter and not the thickness. Where there are a difference in the thickness of the bushing is in the model of the truck. Now some may need to chime in here as I have not mapped this all the way out as yet but the C30 bushings are most def different than the ones for the C-10's. And the C and K series seem to be different so this is where some of the difference might come in.
Now what I would do is to hang the front bumper to see if the front is too high or the cab is too low.
Yes and I drum this into my dad's head every time he wants to try to "make "something fit you can't move one parts problem with out moving the problem farther down the line, and if you keep going by the time you get to the bumper you are liable to have a huge honking mess on your hands trying to line anything to anywhere near close.
So if the bumper doesn't look right when you sit it up on the brackets get some core support mounts that are one inch thinner than the ones you have now and you'll be good to go. If that makes any sense,and your frame isn't tweaked a little but I don't want to freak you out or panic you it sounds just like it is as simple as the wrong rubbers on the core support mounts.
Normally the frame horns are typically referred to as the forward part from the forward most cross member. Good luck and happy sanding. Jim

Thanks for your reply, and thanks for correcting me on my terminology! Yeah, I am worried about just moving the problem down the road. You can only kick that can so far before you have to pick it up right? If I take an inch out of the core support mounts they would be just a washer. Maybe that is okay??? don't know. don't know if that will be an issue with the core support, or with the bumper. Thanks again.

[hugger6933]

Well I just looked the front bumper brackets are the same the years but different for the series between 2 and 4 wheel drive. That may be something to look into on the bumper the 4X4 brackets being different than the 2 wheel drive ones but I know that doesn't throw off the front when the bumper is laying on the shop floor. I still think the answer is gonna lie in the thinner core support bushings or thicker ones under the front of the cab or the combo of both. Did the ones for the cab have two different thicknesses? Were they marked as to location? I'm not trying to confuse just spit balling trying to throw some things out hoping something might stick to the wall. Jim

[BrianG]

Originally Posted by hugger6933

Well I just looked the front bumper brackets are the same the years but different for the series between 2 and 4 wheel drive. That may be something to look into on the bumper the 4X4 brackets being different than the 2 wheel drive ones but I know that doesn't throw off the front when the bumper is laying on the shop floor. I still think the answer is gonna lie in the thinner core support bushings or thicker ones under the front of the cab or the combo of both. Did the ones for the cab have two different thicknesses? Were they marked as to location? I'm not trying to confuse just spit balling trying to throw some things out hoping something might stick to the wall. Jim

I am pretty sure that the front cab mounts are all the same. If I were to add shims there, then sure that what help the issue with aligning the fenders to the cab, however it would also cause the body line to be out unless I follow it all the way back. And maybe that has to be done? I agree that I think the thinner core mounts are a possible solution. Part of the reason for this thread is to find out if putting in thinner front mounts is a viable solution, or will it only lead to other issues with the core support or the bumper not fitting correctly. I know other members have had this same issue. If the thinner core mounts fixed this for them without them having to do to many other mods. Hopefully some them will be able to shed some insight into this.

[FirstOwner69]

Originally Posted by BrianG

Funny! I just sent you a PM actually. I didn't see that you had replied, but did find a post where you also had some issues. It is a 69 1/2 ton 4x4. But it is definitely a Frankenstein truck. I believe the frame is 69 or later because it has the larger holes for the core support mounts.

I think at this point, I'm not really looking for what 'should' be there as much as will the 67-68 mounts work without other issues such as the bumper. Will the 67-68 core support mounts actually lower the core support closer to the frame, and will this be an issue.

I see you ended up using 67-68 core support mounts. How did this end up working for you? Any issue that you can share with the installation, or have you had any issues since? Did it help correct the alignment between the fenders and the cab? Thanks!

For the record, my truck is a 69 3/4 ton 2WD produced the second or third week of December, 1968. I'm 95% positive that the truck came from the factory with the 67/68 style core support mounts. The only reason I'm not 100% sure is that I was hit in the left front in 1972, and minor damage was done to the left front of the core support. The frame was not damaged. I don't believe the core support was removed from the truck when repaired, but when I did the restoration the left mount was assembled differently from the right mount. The core support brackets on the frame appear to have the larger hole and are basically flush with the top of the frame (see 1st pic below). When I did the resto, I replaced the core support with one from a 70, 71 or 72 and used new rubber cab and core support mounts that were the original style. The cab mounts were those specified for 3/4 ton and 4X4 trucks only. I ordered core support mounts for 69-72 trucks as well as those for the 67/68s.

I first used the 69-72 mounts and had a gap problem similar to yours. When I examined the repro 67/68 mount kit, I noticed that the washers supplied were a smaller diameter (too small for the frame bracket holes) than those original to my truck. This would be consistent with the belief that 67/68s had smaller bracket holes. So, I installed the 67/68 kit with my larger washers. The gap was corrected after applying more torque than specified (see 2nd pic). The bumper alignment is great (see pic 3).

[wannabefastcrf]

I had a similar issue and I used a saw to trim 1/4 of an inch off the core support rubber mount.

[BrianG]

Originally Posted by FirstOwner69

For the record, my truck is a 69 3/4 ton 2WD produced the second or third week of December, 1968. I'm 95% positive that the truck came from the factory with the 67/68 style core support mounts. The only reason I'm not 100% sure is that I was hit in the left front in 1972, and minor damage was done to the left front of the core support. The frame was not damaged. I don't believe the core support was removed from the truck when repaired, but when I did the restoration the left mount was assembled differently from the right mount. The core support brackets on the frame appear to have the larger hole and are basically flush with the top of the frame (see 1st pic below). When I did the resto, I replaced the core support with one from a 70, 71 or 72 and used new rubber cab and core support mounts that were the original style. The cab mounts were those specified for 3/4 ton and 4X4 trucks only. I ordered core support mounts for 69-72 trucks as well as those for the 67/68s.

I first used the 69-72 mounts and had a gap problem similar to yours. When I examined the repro 67/68 mount kit, I noticed that the washers supplied were a smaller diameter (too small for the frame bracket holes) than those original to my truck. This would be consistent with the belief that 67/68s had smaller bracket holes. So, I installed the 67/68 kit with my larger washers. The gap was corrected after applying more torque than specified (see 2nd pic). The bumper alignment is great (see pic 3).

Thanks! That information and those pictures help a lot. I am going to order core support mounts for a 68 and then might have to pick up some large washers as well. You're truck looks really nice. I home mine ends up as nice when its all done.