Joe Lucia - correct Front Shock Absorber configuration (paint & hardware), 1965-1969

[Scott S.]

Front Shock Absorbers (1965-1969, maybe 1970+)


Joe,

If you feel like commenting on correct shock absorber configuration, I have a few questions



1) The first picture below shows the AC Delco 88947653 front shocks and associated hardware that came in the box. If this is still the currently recommended shock for a '67 that will be driven, then my first question is about the correct application of Quanta gray shock-absorber paint. I read in another post of yours that the front shock lower bushing, being part of the shock absorber assembly, was painted gray along with the rest of the shock absorber. So I mask off the top stud/spindle and spray the whole rest of the front shocks with a few coats of gray paint, including the entire lower bushing and steel area where the lower shock bolts attach?







The UPPER bushing is GM #3790341. This is a special bushing which is more-or-less flat on the top and configured with the "annular ring" (like most common shock upper bushings as supplied with shock hardare packages that are included with shocks).

Does the larger rubber bushing in pictures #3 and #4 below look correct for the Upper (above the frame) rubber bushing (GM #3790341)? If so, should it be oriented with the beveled edge fitting into the underside of the large washer/retainer (GM 3790342)?




Thank you,

Scott

[Scott S.]

Re: Joe Lucia - correct Front Shock Absorber configuration (paint & hardware), 1965-1

Front Shock Absorber, Top hardware, Lower Rubber Grommet & Lower Retainer

[Joe L.]

Re: Joe Lucia - correct Front Shock Absorber configuration (paint & hardware), 1965-1

Front Shock Absorbers (1965-1969, maybe 1970+)


Joe,

If you feel like commenting on correct shock absorber configuration, I have a few questions

While searching the archives for information, I found several posts of yours, including a detailed post from 1999, but the TDB software won’t allow me to quote or post in a Thread that far back. I recently purchased two front AC Delco shock absorbers (P/N 88947653) and two rear shock absorbers (AC Delco P/N 88945172), and would like to configure them as close to original as I can.

1) The first picture below shows the AC Delco 88947653 front shocks and associated hardware that came in the box. If this is still the currently recommended shock for a '67 that will be driven, then my first question is about the correct application of Quanta gray shock-absorber paint. I read in another post of yours that the front shock lower bushing, being part of the shock absorber assembly, was painted gray along with the rest of the shock absorber. So I mask off the top stud/spindle and spray the whole rest of the front shocks with a few coats of gray paint, including the entire lower bushing and steel area where the lower shock bolts attach?


2) From another post, you mentioned the original heavy duty front shock TOP nut was black phosphate, 3/8-24 thread size, 21/64” thick, either 5/8” or 11/16” across-the-flats, as opposed to the normal 9/16” ATF measurement for a standard 3/8” thread-size nut.

The front top shock nuts I received from LIC (part of LIC #49-18 kit) appear to be standard Hex nuts, and they are 9/16” ATF (picture #2 below). The original front top shock nut listed in the AIM is GM #1365067 (UPC 3-A4, Item 1), but is no longer available through GM. Both for correct configuration and as a safety issue, I would like to get a part that looks close to original and has the quality/strength characteristics of the original heavy duty nut. Any suggestions?


3) I have the large upper Retainers (GM 3790342), but I am unclear about the other three remaining parts. The examples that came with the new AC Delco shock absorbers seem to match a description you gave in (still another) thread: “The UPPER bushing is GM #3790341. This is a special bushing which is more-or-less flat on the top and configured with the "annular ring" (like most common shock upper bushings as supplied with shock hardare packages that are included with shocks).” (Joe Lucia)

Does the larger rubber bushing in pictures #3 and #4 below look correct for the Upper (above the frame) rubber bushing (GM #3790341)? If so, should it be oriented with the beveled edge fitting into the underside of the large washer/retainer (GM 3790342)?


I have a couple questions about the rear shocks too, I’ll start a separate Thread for the sake of clarity.


Thank you,

Scott

Scott------


1) The painting of the front shocks should be done as you describe;

2) The nuts used for the upper front shock are as I previously described. However, I am not 100% sure of the across-the-flats dimension as I do not have GM specs for this particular nut and I have no NOS examples of this nut to measure. I do know, though, that the nut was classified as a heavy-duty nut and was of GM 280M material grade (SAE grade 5). I also know that the 5/16-24 nut of the same part number series had a 9/16" across-the-flats dimension which is one size larger than standard 5/16-24 nuts. I do not know where to obtain a nut of the original configuration and finish. GM says that nut GM #225854 will replace the original nut for SERVICE. This nut is of 9/16" across-the-flats dimension but of GM 301M material grade and thus stronger than the original nut. It is not classified as a heavy duty nut, per se, but the fact that GM catalogs it for the application should ease any worry you might have about its suitability. It's still available from GM but is supplied only in a package of 25. By the way, this nut is primarily used as a connecting rod nut so its strength should not be in question for this application;

3) The larger bushing you show should work just fine for the upper shock bushing. The beveled edge should be oriented upward, interfacing with the convex washer/retainer.

The retainers shown in either your first post or second post were not originally used for ANY shock application, upper front or lower rear, for ANY 1965-82 Corvette. Similar retainers have been supplied, though, with EVERY SERVICE shock ever sold by GM or Delco for any 1963-82 Corvette application.

[Scott S.]

Re: Joe Lucia - correct Front Shock Absorber configuration (paint & hardware), 1965-1

Scott------


1) The painting of the front shocks should be done as you describe;

2) The nuts used for the upper front shock are as I previously described. However, I am not 100% sure of the across-the-flats dimension as I do not have GM specs for this particular nut and I have no NOS examples of this nut to measure. I do know, though, that the nut was classified as a heavy-duty nut and was of GM 280M material grade (SAE grade 5). I also know that the 5/16-24 nut of the same part number series had a 9/16" across-the-flats dimension which is one size larger than standard 5/16-24 nuts. I do not know where to obtain a nut of the original configuration and finish. GM says that nut GM #225854 will replace the original nut for SERVICE. This nut is of 9/16" across-the-flats dimension but of GM 301M material grade and thus stronger than the original nut. It is not classified as a heavy duty nut, per se, but the fact that GM catalogs it for the application should ease any worry you might have about its suitability. It's still available from GM but is supplied only in a package of 25. By the way, this nut is primarily used as a connecting rod nut so its strength should not be in question for this application;

3) The larger bushing you show should work just fine for the upper shock bushing. The beveled edge should be oriented upward, interfacing with the convex washer/retainer.

The retainers shown in either your first post or second post were not originally used for ANY shock application, upper front or lower rear, for ANY 1965-82 Corvette. Similar retainers have been supplied, though, with EVERY SERVICE shock ever sold by GM or Delco for any 1963-82 Corvette application.

Thanks again Joe, I'll order correct front lower retainers and see if I can find the top nuts without springing for a 25-pack.