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body to frame mounts questions

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Old 06-03-2010, 06:45 PM
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Default body to frame mounts questions

So, finally figured out why the bumper won't sit straight........the truck sits about an inch lower on the driver side than on the passenger side. So, I need new bushings.

Here's my questions:

1) LMC sells a kit for $220 that seems to include everything: nuts, bolts, the whole nine yards. Do I really need all that? Or can I buy just the upper and lower cushions and reuse the nuts and bolts I have?

2) LMC's diagram shows 4 body mounts on each side in the cab area. It also shows a 5th mounting point they are calling radiator core supports. Is this part of leveling the body or can I just skip these?

3) What's the best way to go about this? Can I do them two by two, jacking up the body as I go and slipping them in? Perhaps undoing all of them and starting at the front by the firewall and working back?
 
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Old 06-03-2010, 06:57 PM
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Most the time you can't reuse the bolts cause they break. Also if your front corner is sagging your core support itself might be rotted and cracked my s10 is the same way. I did body mounts on a 84 k5 years ago and every single bolt broke off
 
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Old 06-03-2010, 07:00 PM
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Have you measured the distance of both sides of the frame to level ground? The bumper is attatched to the frame so, basically, you're saying the body itself is tilted and making it look like the bumper is crooked? You should be able to start at the front and work your way back replacing the bushings. if the bolts are in good shape you should be able to reuse them, I'd personally put new lock washers on just to be safe.
 
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Old 06-03-2010, 07:18 PM
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Have you inspected the body to make sure that it isn't sagging over the bushings? Rust likes to eat at the body supports at the mounts...

To replace them, you would jack up on side of the body and do all of the mounts on that side. You may want to have everything loose, but I would not remove the bolts from the other side just to keep everything where it's supposed to be.
 
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Old 06-03-2010, 09:33 PM
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i have the same issue with the drivers side sitting about 1 inch lower then passenger, and it is my core support has rusted through... body mounts don't normally give away that much.. but i have seen it on some occasions... as for the re-using... i would not reuse them... the chances of being able to re-use is very LOW... seeing they tend to snap off when you apply pressure...

check the core support closely!!!! there like 120 bucks from LMC also

hope this helps

Ck1500
 
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Old 06-03-2010, 10:08 PM
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swartlkk - yes i have, the body is rust free around the mounts and was rust free in general.

Ck1500 / everybody:

Let me clarify one thing really quickly before I freak out about core supports.

These are the measurements from the ground to the top of the wheel well arches. Also, NewFirstGen, yes, I have measured the frame and it is straight and level.

32.25" [------------] 33"

24" [------------] 25"

So, the front end is only sagging 3/4" while the rear is sagging an 1", which led me to believe it was simply the mounts. Now, however, I'm going to be dumb, the core support is where??
 
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Old 06-04-2010, 06:44 AM
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Measure from the axle up to the frame on both sides just to be sure that the springs aren't sagging in the rear (somewhat common problem) or that you do not have a broken leaf.

You also should be able to measure the mounts from the body to the frame and compare side to side.

The core support is the header panel in the front behind the grill that supports the headlights, radiator core, and the front of the fenders.
 
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Old 06-07-2010, 03:37 PM
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OK, so I reinspected the truck this morning and measured and checked everything I could. However, now I'm more confused than I was before.

I did a very thorough measuring and these are the numbers I came up with.

1) Back bumper sits level on both sides with the ground.
2) The frame on the back sits level with the ground
3) The frame to the body measures 1 inch on both sides at the highest point of the frame directly above the axle
4) After, making sure the tires were pressured up the same on all sides I remeasured the wheel wells and found that the entire driver side is sitting more or less about 3/4/" down.
5) Inspected the core support and found some rust on the bottom, but some sandpaper showed it to be surface only. However, maybe I'm not checking it properly? I checked all the way underneath and the core bushings and mounts are in good condition and not collapsed.

I'm starting to get frustrated because I'm quickly running out of reasons why this is happening. Thanks for all the help.
 
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Old 06-07-2010, 03:55 PM
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Let me see if I can dig up a picture of the mounts on my '74 to show you where I meant for you to measure...

Ok, so here are a few shots of my K5 showing some of the body mounts.

Rear Mount:

Middle Mount front of bed/behind front seats (viewed from L/R side respectively):

Front Mount Under Core Support:

Middle Mount middle of bed above axle:

Front cab mount (doesn't show how it attaches):


Measure each body mount from the location where the mount is on the frame up to the location where the mount ties into the body.

Then measure from the top of the axle straight up to the bottom of the frame at all 4 corners and from the bottom of the axle to the ground. Compare all of your measurements side to side and the cause should become apparent.
 
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Old 06-10-2010, 02:37 PM
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Sigh...Ok.

Body mounts are good and left side springs are sagging. Can these be re-arced by 1/2" or can I get helper springs for the front and rear?

Also, bumper mounts ARE bent, which led to the whole body mount debacle.

Thanks for all the help guys.
 


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