'63 Rubber Cushion on Crossmember Over Rear Axle

[Norm B.]

I have taken the body off my '63 coupe primarily for frame repairs but I will also be freshening things up where appropriate. While I am in the dismantling stage I am cataloguing everything as it comes off and making a shopping list of what needs to be ordered. I have been unable to find out anything about the two rubber cushions for the body that sit on the frame crossmember that goes over the rear axle. I have looked in the usual catalogues from the aftermarket folks and I have gone through the assembly manual to no avail. Even though they seem to be in good shape and are still very securely attached I do not believe they will survive the preparations for the frame repairs. I am anticipating having to replace them. Can anyone tell me; i) What are they called? ii) What material was used to attach them to the crossmember? iii) Where can I get them?

[Duke W.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

My SWC always had a low frequency drumming resonance at about 2000 RPM. It wasn't until I got an AIM back in the seventies that I realized that those rubber blocks were never installed at the plant in my mid-March built car, but I believe they should have been at that point in production. A search of the Corvette P & A catalog came up blank, and the part number in the AIM was not in the system.

So I fabricated my own from thick, dense foam rubber matting.

Their purpose is to provide support for the large flat panel at the rear of the luggage compartment, so it doesn't develop a low frequency drumming excited by the exhaust system frequency. The material I used not only provides support, but also damping.

They're glued onto the cross member, so you might be able to remove them with a sharp scrapper and reuse them, and the glue may be soluble in mineral spirits or denatured alcohol. They appear to be in good shape.

Duke

[Frank D.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

Rural King has very dense rubber matting that is used in horse trailers and the like, lasts for years but you might have to buy an entire sheet just for those small pieces...

[Norm B.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

Thanks Duke, so I am not blind, there is essentially just no information on them to find. I can see the imprint on the underside of the luggage compartment where they have been supporting it so they have been doing their job. They are in excellent shape, not dried out and crumbling like most other similar rubber material on the car and the attachment to the crossmember is still rock solid. I guess the best approach is try to save them and reuse them. I wonder what kind of adhesive they used because whatever it was held up well for 56 years.

[John F.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

Corvette Central has body mount kits, but doesn't show all the pieces. Part #182005. Just pulled up a picture on their website. The two cushions are there.

[Richard G.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

All the body mount kits I identified didn't include the 63 only inner mounts. (The round one near the tunnel)
You may have to reuse them also.

[David H.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

I have taken the body off my '63 coupe primarily for frame repairs but I will also be freshening things up where appropriate. While I am in the dismantling stage I am cataloguing everything as it comes off and making a shopping list of what needs to be ordered. I have been unable to find out anything about the two rubber cushions for the body that sit on the frame crossmember that goes over the rear axle. I have looked in the usual catalogues from the aftermarket folks and I have gone through the assembly manual to no avail. Even though they seem to be in good shape and are still very securely attached I do not believe they will survive the preparations for the frame repairs. I am anticipating having to replace them. Can anyone tell me; i) What are they called? ii) What material was used to attach them to the crossmember? iii) Where can I get them?

Norm

Any rear tunnel body wear - evidence of rubbing by rear universal joint? If so, rubber pieces may have been installed to address body sag. Reference CF thread below.


https://www.corvetteforum.com/forums...y-sag-fix.html

[Harry S.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

LIC has them

BODY MOUNT RECTANGULAR RUBBER BLOCKS (2)	Continue Shopping
Section - Part# #/Car Description Year Set/Ea Price Qty 53-01K Body Mount Rectangular Rubber Blocks (2) 63 Pair $16.00 Add Click thumbnails below for larger version

[Norm B.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

Thanks Harry, I can't remember if I looked at LIC but if I did I must have missed them. At least I know where I can get them now if I need them. I knew someone would come through on this board.

[Norm B.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

No, no evidence of anything like that. These appear to be original to the car and there is nothing to indicate they were added later.

[Duke W.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

Thanks Duke, so I am not blind, there is essentially just no information on them to find. I can see the imprint on the underside of the luggage compartment where they have been supporting it so they have been doing their job. They are in excellent shape, not dried out and crumbling like most other similar rubber material on the car and the attachment to the crossmember is still rock solid. I guess the best approach is try to save them and reuse them. I wonder what kind of adhesive they used because whatever it was held up well for 56 years.

Any "weather strip" cement should work fine. Those will hold them in place, and once the body is on the cement and compression will keep them there forever.

At 16 bucks for a pair, I'd reuse the originals. Make sure you measure their locations so you know where to reinstall them when the frame is done.

Duke

[Duke W.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

All the body mount kits I identified didn't include the 63 only inner mounts. (The round one near the tunnel)
You may have to reuse them also.

I found those MIA from the P&A catalog, too, and I recall I found a "rubber donut" about the same size that worked. Those are actually not body mounts. They are a frame reinforcement to the inside seat belt anchors. Interestingly, the outboard seat belt anchor has no reinforcement. The belt is just bolted to the steel gusset that's riveted to the fiberglass. I always wondered what the engineers were thinking.

Later C2s have cable reinforcements to the frame on all four seat belts anchors.

Duke

[Norm B.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

I am with you on reusing them too if I can Duke. For me it is $16 + Shipping + U.S. Exchange + the usurious UPS Brokerage fee. I rarely buy from LIC because they will only ship to Canada via UPS. Corvette Central tends to get the bulk of my business as they also act as the broker. For the most part though I either order to pick up in Carlisle or wait until I am doing the snowbird thing in Florida.

[Frank D.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

If you read the narrative in this link, the mounts do appear in the 63 manuals, in a photo at least:

https://shop.docrebuild.com/1963CorvetteDifferentialtoBodyMountRubberShim2PieceSetReproOfGM.aspx

Now I'll have to look at my coupe to see if they're there - should be, the body has never been off.

[Timothy B.]

Re: '63 Rubber Cushion on Crossmember Over Rear Axle

Norm,

Get a nice sharp putty knife and work them loose, I would reuse the originals for sure. Super weatherstrip adhesive works well, put some on the frame then on the bottom of the cushions and after it tacks off stick them together.