Core Support Mount Differences?

[71meangreenc10]

Originally Posted by K15

Just to confirm, if I'm installing a 67-68 GMC core support In a 72 GMC frame I use the 72 bushings. I suppose I'll find out eventually when I put the fenders on. Won't be for a while but I'll post results when it's done.

That is what I would start with.

Smitty

[LockDoc]

Originally Posted by K15

Just to confirm, if I'm installing a 67-68 GMC core support In a 72 GMC frame I use the 72 bushings. I suppose I'll find out eventually when I put the fenders on. Won't be for a while but I'll post results when it's done.

That would be correct.

LockDoc

[K15]

Thanks, glad I looked into this, would have hated to find out the hard way.

[Richard]

Originally Posted by K15

Just to confirm, if I'm installing a 67-68 GMC core support In a 72 GMC frame I use the 72 bushings. I suppose I'll find out eventually when I put the fenders on. Won't be for a while but I'll post results when it's done.

That should be correct. As I understand and was noted difference is where the bracket is mounted on frame, not in core support. Differences in headlight buckets on Chevy's as noted. Also note that lower rubber on 4x4 is different than 2wd on 69-72. The 4wd version is more of a puck and 2wd is cone shaped. While I tend to prefer forum venders they do not seem to carry a 4wd core support mount, was told 2wd mount clears bumper brackets by one. My last choice for parts, LMC does offer the correct mounts for rad support. Be wary of their cab supports though. Seen a few posts that they are not the correct height. I can confirm this this as I had them.

[special-K]

He nailed it in post #8

Originally Posted by Green Machine

The core supports are really the same dimension wise, it the head light bucket thing that is different. The key here is to use radiator mount bushings that match the FRAME, not the SUPPORT. 67-68 used the thinner washer type setup with a small hole in the frame, AND the metal supports on the frame are mounted higher. 69-72 went with a larger hole and taller bushing type mount and the frame mounts are located lower on the frame to make up for the taller rubber bushings. Hope that helps.

[LockDoc]

Originally Posted by Green Machine

The core supports are really the same dimension wise, it the head light bucket thing that is different. The key here is to use radiator mount bushings that match the FRAME, not the SUPPORT. 67-68 used the thinner washer type setup with a small hole in the frame, AND the metal supports on the frame are mounted higher. 69-72 went with a larger hole and taller bushing type mount and the frame mounts are located lower on the frame to make up for the taller rubber bushings. Hope that helps.

Originally Posted by special-K

He nailed it in post #8

Not really, the frame brackets are not in different locations on the frame, they are all the same. I don't know about the 4x4's but the '67-'72 2wd are in the same location. The first picture is a '67-'68 frame and the second picture is a '69-72 frame. They are both even with the top frame rail.

LockDoc

[K15]

I've got a welder so it's gonna fit one way or another.

[special-K]

Well, he nailed what you need to know about which core support mounts to use and differences in core supports. The bracket location is irrelevant anyway. We just need to know it's the frame you go by when buying core support mounts, no matter which core support is being used. K15, no need to change a thing. GM made up any differences in the mounts.