Shock Absorber Nut

[Camarocards]

I was just about ready to install my front spiral shocks and realized that I don't have the nut that attaches the top of the shock to the subframe. On page 61 of the '68 AIM, it lists this nut as part number 1365067. I looked in the AMK catalog and unfortunately they don't list it. I already have the grommets and retainers so all I need is the nut.

Does anyone know what the dimensions and finish are of this nut? Anything special about it?

[bertfam]

1365067 was superceeded by 3866766 which is still available from your local GM parts department, but isn't the same finish as the originals. The original nuts were 3/8-24, approx 1/4" (?) deep and cad plated.

Ed

[Camarocards]

Thanks Ed. Yes, I did see that it was superseded but was not aware that it was cad plated.

Do you know if this nut is the short "jam" style nut (which measures  approx. .221 inches thick) or is it a standard nut (which measures approx. .323 inches thick)?

Thanks,

Bob

[bertfam]

Jerry, Troy, John or one of the other guys can probably answer better than I, but I "believe" it's the .221" (don't quote me though). I'll ask Jerry and Troy.

Stay tuned...

Ed

[bertfam]

Bob, I had an ah-ha moment a few mintues ago. My 69 Corvair still had its original spiral shocks on it when I bought it. I had to replace them a few years later (one was leaking), but I kept them anyway. Here's a picture of the original nut!

You'll note it's (approx) 5/16" thick, but UNLIKE a regular not, there's absolutely NO bevel on the edges. Straight cut all the way around. The part number for the Corvair (and most all GM products of the 60's) is the same, so I'm certain it's "correct". All 4 shocks have the same nut on them.

Ed

[bertfam]

Here's a picture of one that's in a little better shape. You can see what's left of the cad under the grease and rust.

Ed

[Camarocards]

Ed,

Very interesting!

So it looks like the nut is a "standard" thickness (5/16") nut but with no bevel.

I ran across this Grade 8 yellow zinc plated nut (yes, I know major overkill!) at Pep Boys last night. I realize that is not cad plated and in light of your recent post, has the bevel on it but it gets me a little bit closer in appearance to having the correct nut.

I suppose I could go to my local Chevy dealer and order the superseded nut, strip the plating and then have it cad plated. I was just hoping for an easier solution. 

Carlisle is only a week away so I'll have a look at some cars there to see what is being used.

Maybe other members could also chime in and post what is on their car.

Many thanks for all your help!

Bob

[Mike S]

 I have a pair of NOS shocks in my shed collecting dust and it has the hardware still attached.
These have never been mounted.
The P/N is 3192831 and are "TM" shocks dated 296-67
The nut looks like the one Ed posted and looks to be zinc plated.
Hope these pictures help.

Mike

[Camarocards]

Thanks Mike. I think we're getting closer.

With what both you and Ed have found, it would appear that a "standard" 5/16" nut was used, albeit without the bevel.

I guess the only remaining question is whether or not this nut was cad plated or zinc plated.

Thanks,

Bob

[JohnZ]

I guess the only remaining question is whether or not this nut was cad plated or zinc plated.

Thanks,

Bob

Hardly ANYTHING was cadmium plated - most fastener drawings gave the supplier the choice of cadmium or zinc plating, and zinc was FAR less costly than cad; when piece cost was quoted in tenths of a cent, suppliers hardly ever chose the more costly option. Cad plating disappeared entirely from automotive applications when it became known that cadmium was a carcinogen.

[Mike S]

Hi Bob,

  The nut looks to have the same plating as the rubber compression disk, zinc.
From past zinc vs. cad plating questions in CRG on various fastener finishes topics, John Z stated cad plating wasn't used often and one of the concerns were health hazards.

Mike
 

[z28z11]

More original pics - 40,000 mile Chevy II rears, same nut -

Regards,
Steve

[Camarocards]

Many thanks to all for the replies.

Looks like zinc plating is the consensus. I think I'll run down to the local Chevy dealer on Monday and order a handful of the superseded part number and see what they look like. Hopefully it'll be a zinc plated nut without the bevel and dimensionally correct.

Thanks,

Bob

[bertfam]

Ok, the book is probably wrong then and it must be zink plated. Which makes more sense, especially going by what John said.

By the way, Bob, the show isn't at Carlisle, it's at Frederick, MD. You probably know that and just make a typo.

Ed

[Camarocards]

Ed,

I was referring to the GM Nationals at Carlisle next week. Always a bunch of great cars there to look at.

http://www.ifounditatcarlisle.com/ce/events/gm-nationals/

Bob