Radiator Support Body Mounts

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Doppleganger

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Having a blonde moment.....

IIRC the 2 donut mounts that go under the radiator support are different from the cab mounts - yes? If so, in what way? Or were the bolts just a different length? Or both?

I'm trying to collect all the randomly stashed parts and brackets to start assembling the front end - rad support, radiator, condenser, fans, etc to pick up some major storage room. Trying to remember the details but me taking mental notes is like writing with a ball point pen on wax paper.

Thx.
 

PrairieDrifter

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Just the bolts are a different length I do believe.
 

CalSgt

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Having a blonde moment.....

IIRC the 2 donut mounts that go under the radiator support are different from the cab mounts - yes? If so, in what way? Or were the bolts just a different length? Or both?

I'm trying to collect all the randomly stashed parts and brackets to start assembling the front end - rad support, radiator, condenser, fans, etc to pick up some major storage room. Trying to remember the details but me taking mental notes is like writing with a ball point pen on wax paper.

Thx.
I ordered the good mark ones from Summit, short ones for core support and front of cab and a pair of tall ones for the rear of the cab. The good mark mounts look almost identical to the ones AMD sells. My truck is an ‘80 so it might be different for the ‘81 and newer bodies.

The bolts they supplied were just a tiny bit short for the core support, but I was able to compress the bolt head to get the nut started. Tightened the nut to compress the rubber down the rest of the way, once fully tightened there are 2 threads sticking out of the top side of the nut.

https://www.summitracing.com/parts/GMK-4144990731S
 

Doppleganger

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I have the mounts - bought real rubber ones from (cant remember ATM) but took a good while to get them and they are every bit OE quality).

LMC shows them as 2 different PNs for the bolts and the rubber cushions. I would guess the rad support bolts are longer and the rad support rubber a tad thicker....?! Could swear this came up before but cant find it.
 

CalSgt

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I have the mounts - bought real rubber ones from (cant remember ATM) but took a good while to get them and they are every bit OE quality).

LMC shows them as 2 different PNs for the bolts and the rubber cushions. I would guess the rad support bolts are longer and the rad support rubber a tad thicker....?! Could swear this came up before but cant find it.

Shoot, sorry not much help here. Even using same mounts and bolts on mine the core support mounts seemed to want a little more bolt than I had so your logic makes sense.
 

hogdaddy

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I used slightly longer than stock stainless steel bolts for front core support. I believe they were about 6" long but I can check tomorrow.
 
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hogdaddy

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Stock length was 5" but they rusted bad in the middle of bolt was why I went to Stainless Steel and I had to order them from one bolt houses online.
 

Camar068

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put a load of anti-seize on those bolts
 

Doppleganger

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put a load of anti-seize on those bolts
I actually ran a tap through everything to straighten and clean the threads once I got the originals out (they needed it too). They'll get lathered good with anti seize or some synthetic grease before going back together.
 

Doppleganger

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Just the bolts are a different length I do believe.
Just to wrap this thread.... @PrairieDrifter - you are correct. I found all my new mounts - the rubber is the same and the only difference is the length of the bolts. The radiator support bolts are longer.
 

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I used slightly longer than stock stainless steel bolts for front core support. I believe they were about 6" long but I can check tomorrow.
You need to be careful using stainless bolts on anything requiring pull out strength. 304 stainless is the equivalent of using a grade 2 bolt. You may be ok using 316, it is equivalent to about a grade 5, but definitely don't use stainless for your cab mounts
 

hogdaddy

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You need to be careful using stainless bolts on anything requiring pull out strength. 304 stainless is the equivalent of using a grade 2 bolt. You may be ok using 316, it is equivalent to about a grade 5, but definitely don't use stainless for your cab mounts
They were 316 stainless from one of the bolt houses. Only one available at the time were 6" length and could cut an inch if needed.
The oem bolts rusted badly in the middle, I doubt they were adequate.

F593C is 316 stainless.
You must be registered for see images attach

This is the 5" oem bolt.
You must be registered for see images attach
 
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Turbo4whl

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I ordered the good mark ones from Summit, short ones for core support and front of cab and pair of tall ones for the rear of the cab....... My truck is an ‘80 so it might be different for the ‘81 and newer bodies.

Yes this, and there were 2 different sizes for the rear tall mounts, may have changed sooner, 1978?
 

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