C3 Front Suspension Finish

[Michael B.]

I pulled the front suspension down on my 1969 last night to refinish everything in preperation for San Jose. I'm sending most everything out to be stripped so that I can repaint without a POP deduction. I think I have the finishes down but if anyone would like to correct my list feel free. I also understand that different componets (frame, A-arms, brackets) may have a slightly different shade of semi gloss black.

Upper A-Arms.........................................Semi Flat Black
Lower A-Arms.........................................Semi Flat Black
A-Arm Bushings.....................................Natur al
A-Arm Pivot Shaft..................................Natural
A-Arm Pivot Bolts & Washers.............Natural
Lower A-Arm Mounting Bolts..............Natural
Lower A-Arm Mounting Bolt Backing Plate...Natural
Lower A-Arm Bumper Mounting Bracket & Bolts...Natural
Upper Ball Joint....................................... Natural
Lower Ball Joint....................................... Natural
Ball Joint Rivets........................................Natu ral
Spindle........................................... .......... .Natural
Brake Caliper........................................... ..Semi Gloss Black with Natural at Machined Areas
Brake Caliper Mounting Bracket............Natural
Steering Arm............................................ Natural
Rotor Backing Plate.................................Silver Zinc Plated
Tie Rod Ends........................................... Natural
Tie Rod Sleeves..................................... .Natural
Tie Rod Sleeve Nuts & Bolts.................Natural
Sway Bar............................................... ....Natural or Black Dip
Sway Bar Bushing Brackets...................Semi Gloss Black
Sway Bar Bushing Bracket Bolts...........Semi Gloss Black
Springs........................................... ...........Natural
Shocks............................................ ...........Gray
Shock Mounting Bolts............................Black Phosphate

[Michael L.]

Re: C3 Front Suspension Finish

The best guide is what you find on the car if you believe the car to be original. With that being said, the original finish may not be discernable. I cannot swear as to the accuracy of this (not being a judge) so confirm before you commit. Here is what I know about these areas, but more complete discussions of this info can be gleaned from searching the archives for each individual topic:

Upper A-Arms.........................................Semi Flat Black (More like a semi-gloss black, glossier than the frame)
Lower A-Arms.........................................Semi Flat Black (see upper A-arms)
A-Arm Bushings.....................................Natur al (correct)
A-Arm Pivot Shaft..................................Natural (can be natural or painted semigloss)
A-Arm Pivot Bolts & Washers.............Natural (large flat washer natural, bolt and lock washer black phosphate)
Lower A-Arm Mounting Bolts..............Natural (Bolt and serrated washer black phosphate, stover nut cad plated)
Lower A-Arm Mounting Bolt Backing Plate...Natural (Cad plated for plate and bolts)
Lower A-Arm Bumper Mounting Bracket & Bolts...Natural (Cad plated ??)
Upper Ball Joint....................................... Natural (correct)
Lower Ball Joint....................................... Natural (correct)
Ball Joint Rivets........................................Natu ral (correct)
Spindle........................................... .......... .Natural (correct)
Brake Caliper........................................... ..Semi Gloss Black with Natural at Machined Areas (low gloss, almost but not quite flat with natural at machined areas)

Brake Caliper Mounting Bracket............Natural (Zinc plated with a chromate dip i.e. goldish)
Steering Arm............................................ Natural (Natural or black coated from the blackout procedure
Rotor Backing Plate.................................Silver Zinc Plated (actually silver cad plated)
Tie Rod Ends........................................... Natural (correct)
Tie Rod Sleeves..................................... .Natural (natural or black coated from the blackout)
Tie Rod Sleeve Nuts & Bolts.................Natural (bolt black phosphate and nuts cad plated)
Sway Bar............................................... ....Natural or Black Dip (correct)
Sway Bar Bushing Brackets...................Semi Gloss Black (correct)
Sway Bar Bushing Bracket Bolts...........Semi Gloss Black (black phosphate (?? silver cad))
Springs........................................... ...........Natural
Shocks............................................ ...........Gray (blueish/gray- get the paint from Quanta)
Shock Mounting Bolts............................Black Phosphate (see below)

Here is more than you will ever need to know about shock hardware (lifted from a previous Joe Lucia post)

Each shock will come with mounting hardware and bushings. For the rears, you can use the hardware, except for the lower nut and washer. The original lower shock retaining nut was much thicker than a standard nut. This nut, GM #3691530, was still available the last I checked. If you don't already have them, you might want to get some. This nut is about 3/4" thick and is phosphate coated. The nut that comes with the shock kit, which is usually a standard zinc plated nut, will function perfectly, though; it's just not the original configuration. The lower washer was not the plated, flat washer which comes with the kit. Originally, it was GM #3714310, which, the last time I checked, was still available. This washer is a plain steel(rusts), "saucer-shaped", convex washer. It should be installed with the saucer pointing OUTWARD, the opposite of what seems intuitive. You can use the lockwasher from the kit, but it is zinc plated as opposed to phosphate of the original. The original lower rubber bushings were a two-piece design, whereas the replacement shocks will come with a one-piece, already installed bushing. There is NO functional difference between the two types and it is IMPOSSIBLE to tell the difference once installed on the car. Use the bushings as installed.

For the front shocks, the upper hardware is incorrect(but entirely functional). The original upper, upper grommet was GM # 3790341, which is still available. You can use the 6270752 lower, upper grommet supplied with the shock kit. You will end up with 2 left over of these if you obtain the 3790341 upper, upper grommets I described. Also, the original upper retainer was GM #3790342. This retainer is also still available last I checked. It is a large, convex-shaped "washer" with an "oil-penetrant" type finish. It is 1-29/32" outside diameter and 13/32" inside diameter. Originally, the upper shock shaft retaining nut was a 3/8-24 phosphate coated nut. The replacement provided in the kit will be a zinc plated nut. An original style nut may still be available under GM #225854.

[Robert E.]

Re: C3 Front Suspension Finish

I just checked with a local deal and one in Michigan. Both the upper shock washer (3790342) and grommet (3790341) have been discontinued. Would anyone have a line on a set for me or a lead on getting a set?

Robert
41801

The best guide is what you find on the car if you believe the car to be original. With that being said, the original finish may not be discernable. I cannot swear as to the accuracy of this (not being a judge) so confirm before you commit. Here is what I know about these areas, but more complete discussions of this info can be gleaned from searching the archives for each individual topic:

Upper A-Arms.........................................Semi Flat Black (More like a semi-gloss black, glossier than the frame)
Lower A-Arms.........................................Semi Flat Black (see upper A-arms)
A-Arm Bushings.....................................Natur al (correct)
A-Arm Pivot Shaft..................................Natural (can be natural or painted semigloss)
A-Arm Pivot Bolts & Washers.............Natural (large flat washer natural, bolt and lock washer black phosphate)
Lower A-Arm Mounting Bolts..............Natural (Bolt and serrated washer black phosphate, stover nut cad plated)
Lower A-Arm Mounting Bolt Backing Plate...Natural (Cad plated for plate and bolts)
Lower A-Arm Bumper Mounting Bracket & Bolts...Natural (Cad plated ??)
Upper Ball Joint....................................... Natural (correct)
Lower Ball Joint....................................... Natural (correct)
Ball Joint Rivets........................................Natu ral (correct)
Spindle........................................... .......... .Natural (correct)
Brake Caliper........................................... ..Semi Gloss Black with Natural at Machined Areas (low gloss, almost but not quite flat with natural at machined areas)

Brake Caliper Mounting Bracket............Natural (Zinc plated with a chromate dip i.e. goldish)
Steering Arm............................................ Natural (Natural or black coated from the blackout procedure
Rotor Backing Plate.................................Silver Zinc Plated (actually silver cad plated)
Tie Rod Ends........................................... Natural (correct)
Tie Rod Sleeves..................................... .Natural (natural or black coated from the blackout)
Tie Rod Sleeve Nuts & Bolts.................Natural (bolt black phosphate and nuts cad plated)
Sway Bar............................................... ....Natural or Black Dip (correct)
Sway Bar Bushing Brackets...................Semi Gloss Black (correct)
Sway Bar Bushing Bracket Bolts...........Semi Gloss Black (black phosphate (?? silver cad))
Springs........................................... ...........Natural
Shocks............................................ ...........Gray (blueish/gray- get the paint from Quanta)
Shock Mounting Bolts............................Black Phosphate (see below)

Here is more than you will ever need to know about shock hardware (lifted from a previous Joe Lucia post)

Each shock will come with mounting hardware and bushings. For the rears, you can use the hardware, except for the lower nut and washer. The original lower shock retaining nut was much thicker than a standard nut. This nut, GM #3691530, was still available the last I checked. If you don't already have them, you might want to get some. This nut is about 3/4" thick and is phosphate coated. The nut that comes with the shock kit, which is usually a standard zinc plated nut, will function perfectly, though; it's just not the original configuration. The lower washer was not the plated, flat washer which comes with the kit. Originally, it was GM #3714310, which, the last time I checked, was still available. This washer is a plain steel(rusts), "saucer-shaped", convex washer. It should be installed with the saucer pointing OUTWARD, the opposite of what seems intuitive. You can use the lockwasher from the kit, but it is zinc plated as opposed to phosphate of the original. The original lower rubber bushings were a two-piece design, whereas the replacement shocks will come with a one-piece, already installed bushing. There is NO functional difference between the two types and it is IMPOSSIBLE to tell the difference once installed on the car. Use the bushings as installed.

For the front shocks, the upper hardware is incorrect(but entirely functional). The original upper, upper grommet was GM # 3790341, which is still available. You can use the 6270752 lower, upper grommet supplied with the shock kit. You will end up with 2 left over of these if you obtain the 3790341 upper, upper grommets I described. Also, the original upper retainer was GM #3790342. This retainer is also still available last I checked. It is a large, convex-shaped "washer" with an "oil-penetrant" type finish. It is 1-29/32" outside diameter and 13/32" inside diameter. Originally, the upper shock shaft retaining nut was a 3/8-24 phosphate coated nut. The replacement provided in the kit will be a zinc plated nut. An original style nut may still be available under GM #225854.

[Michael B.]

Re: C3 Front Suspension Finish

Corvette Central has the washers but you will have to wirewheel the plating off. The grommets can bearly be seen under the washer so I just used the ones packaged with the new shocks but CC has those in a kit too.


1965-1982SHOCK ABSORBER RETAINER WASHER - UPPER



#572185...6.00PAIR

1963-1982SHOCK ABSORBER MOUNT KIT - FRONT DOES 2 SHOCKS

#581030...10.95KIT

[James B.]

Re: C3 Front Suspension Finish

Americas Finest Corvettes has reproduced the front shock absorber upper retainer (in correct finish). I saw them first-hand on my last visit there and they look great.