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Old Mar 16, 2026 | 04:37 PM
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Default Reinforcement

Guys:
I can’t find GM part # 3976463-4 for a ‘69 coupe (reinforcement found in the assembly manual on page J133, F26, item #3).
Can I substitute a regular washer?


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Old Mar 16, 2026 | 05:25 PM
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Are those two pictures actually related to one another.
This post refers to that part number but it is Not a washer.
Look at post 3.
https://www.corvetteforum.com/forums...kets-69-a.html
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Old Mar 16, 2026 | 06:08 PM
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This is part number 3.

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Old Mar 16, 2026 | 06:26 PM
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Originally Posted by robertea
This is part number 3.
Correct, not a washer as the original poster thinks.
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Old Mar 16, 2026 | 06:50 PM
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Sorry for the confusion.. It's the reinforcement that goes under the 7/16-20 jam nut.


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Old Mar 16, 2026 | 07:17 PM
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Originally Posted by jigoe007
Sorry for the confusion.. It's the reinforcement that goes under the 7/16-20 jam nut.

The part that the red arrow is pointing to is NOT a washer, it's a metal reinforcement PLATE, held down by 3 bolts.
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Old Mar 16, 2026 | 07:24 PM
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This is the reinforcement
Reinforcement
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Old Mar 16, 2026 | 07:52 PM
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Mel,

Not sure that what you posted is the reinforcement being referenced. The one you posted is the outboard reinforcement… The reinforcement in the A.I.M. drawing (3976463-4) is the inboard reinforcement.

Looks like this…



It is reproduced by CSC, but I can’t tell you how well it is done.



Regards,

Stan Falenski
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Old Mar 16, 2026 | 08:08 PM
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Originally Posted by Rowdy Rat
Mel,

Not sure that what you posted is the reinforcement being referenced. The one you posted is the outboard reinforcement… The reinforcement in the A.I.M. drawing (3976463-4) is the inboard reinforcement.

Looks like this…



It is reproduced by CSC, but I can’t tell you how well it is done.



Regards,

Stan Falenski
Either way it's not a simple washer as the OP originally believed.
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Old Mar 16, 2026 | 08:26 PM
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I guess I used the wrong term. Those reinforcements are installed on the car. I need the part inside the red circle at the top right.

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Old Mar 16, 2026 | 09:54 PM
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Originally Posted by jigoe007
I guess I used the wrong term. Those reinforcements are installed on the car. I need the part inside the red circle at the top right.
That part (138494) is an external tooth washer with a 7/16” diameter hole.

Regards,

Stan Falenski
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Old Mar 16, 2026 | 10:32 PM
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Thanks y’all! It’s item 8 that I need. The print is lousy in the manual!
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Old Mar 16, 2026 | 11:35 PM
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