The Stovebolt Site Forums The Shop Area Paint and Body Shop AD Truck - Core Support Mounts

Anyone have an idea what thickness the rubber mount pads are?

I bought some material to make my own, and I could do two layers if necessary.

Section 11, Sheet 2.11 of the factory assembly manual says "shim as required". If you want to put rubber pads in there, you will have to adjust for that.

Nathan - According to the Chevy Master Parts Catalog descriptions, the original rubber core support pads (GM# 3684763) dimensions are 2-1/4" x 1-1/4" but no specified thickness that I could find. Ditto for descriptions from the various regular vendors we tend to use. IIRC correctly they were about 1/4" thick. Jim Carter sells the pads as ME195 for radiator supports that use the two mount system. The FAM shows 2 mount supports used for 3100 - 3600 models and a single center mount radiator support for 3800 - 6000 model trucks, which use a different pad and bolt setup.

I tried to look up the GM part numbers listed in Gord's reference and could not find matches to any of the "shim" numbers except for GM# 366981. That is listed as an AD series truck "cab" body mount shim. Nothing showing it listed for the radiator support.

As far as shimming goes (to help get front sheet metal alignment), the only vendor I found that seems to offer radiator support shims for the AD series trucks is Chev's of the 40's. They don't mention pad or shim dimensions, nor do they indicate how many "shims" are included in their kit???

Hope this helps some.

That does help. I was a little confused by the single vs double mounts, thinking maybe trucks had BOTH types and each served a different purpose. But mine has the double variety which ties out with your research.

The rubber I bought is “baler belt” from the farm store. I like it for this type of thing. It’s 5/16-ish thick.

The body gaps on my truck are far from perfect so probably no need to overthink this. My main goal is just reduce some harshness as there is ZERO remnant of rubber in this area now. I can use plain old body shims if need be.

Thanks!

Most welcome buddy! Merry Christmas!!!

My spare radiator pads are 2" x 2" x 1/4" thick. Hole is around 7/16" in diameter.

Those pads, with or without shims, is about the base of all alignment for front end sheet metal. On the 3100 series, I believe the early version was a single pad, the later years went to dual pad. I could be wrong on that though. I would suggest to install your core, lay your hood latch panel up there, preferably without latch, then lay your hood on top, less hood springs. See how the gaps look at the cowl. Roughly shim as necessary to get good gaps top and bottom. Remove hood and keep building your front end. Later on, with the cowl to inner fender braces in, you can triangulate the front sheet metal and adjust the core with more finesse.

The spacing between the radiator support and the cross member is crucial for properly adjusting the hood.
It won't likely be the exact same gap for every truck. Close enough isn't close enough. It needs to be spot on.
The gap at the rear of the hood and the front of the cowl needs to be between 1/8" and 3/16" and parallel all the way across.

Once you have the hood perfectly adjusted, you are done with it. No more adjustment of the hood will be needed.

Once you are done with the hood, then you adjust the fenders upwards until they match the underside of the hood.

Is there any tweaking tips for the hood latch I have put my fenders back on from doing the floor and cowl area on both sides as well as the outer inner cowl each side was done before taking the other side apart .,the drivers side the floor support was replaced also both cab mounts .The hood latch seems to be off centre with the hood but the hood fits okay at the back and along the fenders .The origional hood latch 4 bolt holes seemed to be enlarged so the latch can be moved over but I have another latch that the holes are smaller so no adjustment there.The brace rods are close to the required measurement and the rad support is a center support type with the bolts in the origional holes .Also just to check which side of the truck is the right side is it right and left when you are sitting behind the wheel or from standing out front looking at the grill .so right would be passenger side and left is driver side ?

Yep the right and left are from sitting in the drivers seat .loosened all the cab mounts and core support re adjusted the support rods and I am a little closer .

The support rod specs in the manual are a good starting point. Don't be afraid to deviate from those specs to align the front clip.
What are your gap measurements for the front and rear cab mounts? You need to have those within the specs in the Manual before you set the hood. Failing to do this will increase errors exponentially for aligning the fenders under your perfectly aligned hood.

Everything lines up okay when the hood is closed but the latch is off and sticks to open. There is no adjustment for the latch unless I open up the holes a tad. The hole in the panel under the latch needs to move over towards the driver side. The hood seems like it comes down crooked, so maybe the hinge is off on the one side. Still messing around with it. The rear cab mounts are new as well as the front but the front seemed a little low so there is another pad under both sides but don’t think the mounts are affecting the front latch. The gap between the box and cab are a little off, but I measured at the back and the same difference is at the back so I think the box is where the difference is from only a bit under 1/4 inch .

Can you loosen the lower radiator support bolts and move the radiator support over? You will likely need to loosen a whole bunch of fender bolts and the cowl-to-radiator support threaded rods to do this.
Before I would do this, I would take two steps back and get the cab height spacing to within specs at all four cab mounts and then start over with the hood adjustment with the hood latch removed and the fender bolts loose and pushed down as far as they will go.
It has been my experience that if one does not do it this way, one will be fighting an uphill battle and end up totally frustrated with the lack of results.

The rad support bolts are loose and don’t think they will move over any more but the rad support is the center only support so it may twist a little to move .The weather took a dip on the cold side so when the temp gets up enough to crawl under I am going to check the measurements of the mounts but I did notice the drivers hinge spring to be higher than the pasenger side so I feel that by lowering the drivers hinge spring it may level the hood on that side and bring the hood pin closer to the hole .in the picture the hood is higher on the drivers side and the tape is we’re the center is we’re the hood pin should be on center .I will update in a few days thanks for the help with this .

To cold out to be in the garage but I lowered the drivers hinge and looks like I am getting closer ,More tinkering on a warmer day