Energy suspension radiator bushing

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wharenj

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Has anyone found that the metal in the bushing is a smaller diameter than the bracket hole? I measure 1 7/16" on the bushing and 1 11/16" on the bracket. The tech at Energy Suspension said it will work but I am not comfortable with that much play.

Also, does anyone know where I would be able to find the factory sleeve? Since the mounts were taken apart 25 years ago, I do not remember where the ones for the cab got to. At this point I am starting to make them but still looking for a source. I have searched the web and contacted my local dealer with no success.
 

75gmck25

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Which radiator bushings are you talking about? Do you mean the ones that hold the radiator support (not the radiator itself)?

I used the polyurethane body mount kit for my '75 K25 and everything fit very well. Are you looking for a factory sleeve that goes around the bushings? I think the kit included everything I needed, including new sleeves, so all I needed for factory fittings was the threaded holes in the cab.

When replacing the bushings on the radiator support it was very hard to reach the bolts and I had to buy a new type of socket to get to them. IIRC the socket I needed was one that slipped over the bolt and then had a six point fitting on top so that you could turn the socket with an open end wrench. I had to use that because there wasn't enough space for a standard deep socket and wrench to fit and turn the nut.

Bruce
 

wharenj

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The bushings are for the radiator support. You can see there is about an 1/8" space around the entire bushing when centered and about 1/4" when moved to the side. The third pic is the bushing in the front cab bracket.


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theblindchicken

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The cone shaped bushing is the lower bushing that mounts under the bracket. The upper bushing is just a standard cylindrical bushing with a washer embedded into it. Washer fits in the hole, lower bushing points down. Large diameter at top, lower at the bottom.

quick text dia:

bolt
washer
Radiator Support
Upper Bushing
Frame plate
Lower bushing
washer
nut

For a bushing sleeve, you could use thinwall tubing. All that sleeve does is ensure that there isn't much slippage between the upper and lower bushings.

For the tools needed, all I used was a 1/2" drive socket wrench with a deep socket to hold the bolt head and a racheting open end wrench for the nut. Worked out perfectly. May be able to use a short socket and a socket wrench on the bottom depending on how large your wrench is.
 

75gmck25

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I took a look at mine, but with the radiator support mounted all I can see is the black rubber on both top and bottom. I don't remember having any play in the bushing, but I replaced them when the complete body was mounted, so visibility wasn't that great.

It makes sense that the bushing should fit relatively tight so that its self-centering. On the other hand, the rubber bushing is the main contact point once its tightened down, and at that point the bushing can't move much at all. You might just sleeve the bushing with something to keep it centered (maybe a thin sheet of flexible plastic or a piece of rubber sheeting wrapped around it?) and then tighten everything down. Thinwall tubing would probably work the best, but it might be a little harder to find the right size.

Bruce
 

theblindchicken

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Took a quick photo of my polyurethane set since they're out for ya. I've got a body lift, but that doesnt change anything. Just a longer bolt.

You can see the lip I mentioned earlier on the bottom of the upper bushing, that fits inside the frame rail and keeps the bushing from becoming misaligned.
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cooperhw

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I noticed the same on my 78. I would not worry too much about it. Just check the side to side measurements before cranking it down. Once tight the core support bushing really only do one thing and that is to keep the front clip attached and tight down to the frame horns. No side to side stresses implied.
 

wharenj

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Thanks for the replies. I was thinking of getting some pipe and cutting a small filler piece to take up the play but now I'm thinking once it is all tightened the space won't be an issue. Still not sure why the piece was not made bigger to accommodate the larger diameter hole.
 

theblindchicken

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Thanks for the replies. I was thinking of getting some pipe and cutting a small filler piece to take up the play but now I'm thinking once it is all tightened the space won't be an issue. Still not sure why the piece was not made bigger to accommodate the larger diameter hole.
The upper bushings have a metal lip that sets into hole. Its designed to use that large hole to center itself on the frame so it doesn't shift around when the frame flexes.
 

Honky Kong jr

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Don't use red use the black ones......you'll thank me for it later.
 

Camar068

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theblindchicken

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lol.....ok why's that? The red more brittle?
If I remember correctly, the black polyurethane bushings usually have graphite infused in them to prevent any squeaking over time whereas the reds typically don't have the added graphite.
 

Honky Kong jr

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If I remember correctly, the black polyurethane bushings usually have graphite infused in them to prevent any squeaking over time whereas the reds typically don't have the added graphite.
You are correct.
 

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