F51 HD Shocks

[Tom R.]

P/Ns 3196957 and 4940459 front/rear) superceded the original F41 P/Ns 3171488 and 3171489 (resp).

But were the 3196957 and 4940459 numbers also the original shock P/Ns for the F51 heavy duty shock absorbers offered in 79-81?

[Joe L.]

Re: F51 HD Shocks

Tom-----

This is a lot more complicated question than it might seem.

First, a little explanation of shock absorber part numbers. PRODUCTION shock absorber part numbers are the part number for shock, as a seperate unit; SERVICE part numbers are the part number for a shock + the rest of the contents of the box in which the shock is supplied. So, in a sense, they are the part number for a KIT (although GM never used that term to describe the shock+hardware unit). The part number on a SERVICE shock supplied in the box with other parts is usually NOT the same as the part number on the box (and in the P&A Catalog). Also, the part number on the SERVICE shock is usually not the same as the part number of the PRODUCTION shock EXCEPT, SOMETIMES for SERVICE shocks sold during the same time period as a certain shock is used in PRODUCTION.

The PRODUCTION part number for 79-80 F-51 front shocks was GM #4984577. The 1979-era SERVICE part number for the F-51 shocks was GM #3196957. As far as I know, the box containing the 3196957 shocks (+ hardware) did not contain a shock with the part number 4984577. However, it's possible that, in 1979, or so, they did. I may be able to confirm that later.

The PRODUCTION part number for 1979-80 F-51 rear shocks was GM #22012402. However, the SERVICE part number for this shock was NEVER GM #4940459. The SERVICE part number for the 22012402 shock was always GM #4993538. This shock was discontinued without supercession several years ago.

[Tom R.]

[Joe L.]

Re: F51 HD Shocks

Tom----

Not quite; forthwith some clarification:

1) The F-51 SERVICE shocks for 79-80 are GM #3196957, front, and GM #4993538, rear. These are the numbers that will be found in the P&A Catalog and on the box which contains the SERVICE shocks + hardware. It is very unlikely that they'll be the same numbers as found on the shocks. Likely, the numbers actually found on the shocks will be some number COMPLETELY different than either the original PRODUCTION part number or the SERVICE part number.

Also, BOTH the GM #3196957 shock absorber and the GM #4993538 are discontinued. The GM #3196957 was discontinued in March, 1999 and replaced by GM #22046803. Many examples of the GM #3196957 carried the part number 4984577 on the shock, itself. I might also add that the GM #22046803 also replaced the standard shock. So, now, the standard and HD shocks "are one". Also, the GM #22046803 is a gas charged shock. Originals, either standard or HD, were not.

The GM #3196957 and its successor the GM #22046803 are the SERVICE replacement FRONT shocks for ALL 63-82 Corvettes with HD suspension, be it F-40, F-41, FE7/F51 or Z-07.

GM #4993538 were the SERVICE replacement REAR shocks for 78-82 Corvettes with HD suspension. They were discontinued without supercession in October, 1992. It will be difficult to locate a set of these. I don't know what part number that these carried on the shocks, themselves.

For judging and 100% "correctness", one should be looking for the PRODUCTION part number on the shocks. However, given the nature of shock part numbers, I could not say with certainty that ALL original, PRODUCTION shock part numbers were the same as that shown in the AIM or other GM PRODUCTION information sources. Production line workers did not refer to part numbers. They referred to a broadcast code label found either on the shocks or the bin they were supplied in. If factory parts personnel knew/were informed that a certain shock part number was equivalent to another and approved by engineering for the application, that same broadcast code would be placed on those shocks and they would be used on the line.

For SERVICE requirements, if you went to a GM dealer's parts department and provided them with the correct PRODUCTION part number you wanted the SERVICE equivalent of, they'd look at you with a bemused and/or perplexed LONG stare. I'll bet that there is not 1 single GM dealership in the country that could tell you the SERVICE equivalent of a PRODUCTION shock absorber part number, particularly for any 53-82 Corvette. As Dr. Rebuild would say..."fuhgeddaboudit". For SERVICE requirement you do as follows:

1) Go to a dealership and ask for the SERVICE shock absorbers for a particular application. Assuming they're willing to look them up without just telling you they're discontinued (a usual assumption on their part), they'll find the correct, current SERVICE shocks and order them for you. It WILL service your application. Chances are the configuration of said SERVICE shocks will be identical or near-identical to the originals EXCEPT for "numbers" and "dates".

OR

2) Go to your GM dealer and provide the current SERVICE shock part numbers for your application. Although the ones shown in your 83 edition of the P&A Cataolg may be discontinued, they'll be able to tell you if supercessive parts are available.

The reason I just mentioned 79-80 in my origianl response was that I didn't bother to check for later/earlier models. I fully expect that the info is the same for 81-82 models, but the PRODUCTION HD shock part numbers for those years MAY be different.

[Larry Beards;ee]

Re: F51 HD Shocks

Tom,

I have a nice clean set of original F41 shocks. The rears are #22025105 and fronts are #22012402. I took them off my Bloomington Gold 1979 L-82 4-SPD in 1988 when the car had 68 miles on it. They have been laying in my garage since. I will be listing these on eBay soon.

Larry Beardslee

[Tom R.]

Re: F51 HD Shocks

Joe & Larry:

First Joe: Appreciate your taking the time to detail those differences and I find it quite instructive. So I had it backwards...took me an evening and morning to digest it all. Production is what I see on the car (as you wrote...makes perfect sense) but "service replacement" is exactly that. In Bowtie judging we're looking for production numbers while in Top Flight service replacement earns points.

Since GM service replacements use one unit for F40, F41,F51, and Z07...what color are they? Early HD shocks were gray while later were black!

Now Larry's numbers jives with those Joe wrote for the front...the 22012402 HD. But the rears are different...4984577 versus 22025105...I think I read that right. The NCRS tech manuals are void of shock P/Ns from 78-82.

[Joe L.]

Re: F51 HD Shocks

Larry-----

Could it be that you have the numbers reversed for front and rear? I have the GM #22012402 as being PRODUCTION REAR shocks.

Also, is this a later build 79? the GM #22025105 could have superceded the 4984577 later in PRODUCTION. Or, the 22025105 could have been an alternate shock used in PRODUCTION.

[Joe L.]

Re: F51 HD Shocks

Tom-----

GM SERVICE shocks pretty much tracked the color used for PRODUCTION during any particular time period. Prior to about 1965, they were black. From about 1965 until the later 70s (I don't know exactly when) they were gray or blue-gray. From the later 70s to the present, they are black.

The above applies to SERVICE shocks obtained through the GM parts system. Shocks obtained through the Delco parts system were many different colors. Red, aqua, and black are a few of the colors. The configuration of the basic shock, though, was usually the same as GM PRODUCTION and SERVICE shocks.

[Larry Beards;ee]

Re: F51 HD Shocks

Joe,

You are right I guess I had them reversed. They are now up on eBay;
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2425804693 If anyone is interested. Yes, my 1979 is the last L-82 4-SPD made early in 1980.

Larry