Topic: 68 C4 transmission finishes

[Stangly]

Hey guys have my tranny apart and would like to confirm the finishes of a few items.  Any input, tips or advice would be greatly appreciated.

1.  Low reverse servo cover has a few ruminants of what appears to be aluminum paint over phosphate.
2.  Breather tube and bracket that attaches to top bolt of LRS cover
3.  Manual shift linkage and kick down lever looks like phosphate & oil
4.  Oil pan cover no finish left to compare bare steel?
5.  Bolts that attach both servo covers & oil pan.

[J_Speegle]

Hey guys have my tranny apart and would like to confirm the finishes of a few items.  Any input, tips or advice would be greatly appreciated.

1.  Low reverse servo cover has a few ruminants of what appears to be aluminum paint over phosphate.

Aluminum paint is likely from an earlier rebuild - often they just rattle can everything after they are done

The reverse servo cover (drivers side one)  should be stamped steel  - unpainted. Think it was just bare oiled steel no plating

2.  Breather tube and bracket that attaches to top bolt of LRS cover

Tube looks to be bare steel or maybe ?  zinc plated - can still make out the lines in the surface material

Clamp appears to be darker  so guessing bare steel (no sign of plating on the ones I'm looking at)

3.  Manual shift linkage and kick down lever looks like phosphate & oil

The shift rod is either heat treated steel or Phosphate - basically the same darkness

Kick and sifter arms  appears to be

4.  Oil pan cover no finish left to compare bare steel?

Just bare steel - possibly oiled originally to reduce the chance of rusting prior to sale

5.  Bolts that attach both servo covers & oil pan.

Looks to be dark finished so phosphate or dark heat treated - both about the sane tone when finished and oiled

Same finish for the band adjusting nuts and rods

[Stangly]

Thanks a bunch Jeff this will get me going in the right direction.

[TLea]

The reverse servo cover (drivers side one)  should be stamped steel  - unpainted. Think it was just bare oiled steel no plating  +1

Tube looks to be bare steel or maybe ?  zinc plated - can still make out the lines in the surface material  Bare steel

Clamp appears to be darker  so guessing bare steel (no sign of plating on the ones I'm looking at)  +1

The shift rod is either heat treated steel or Phosphate - basically the same darkness  heat treated

Kick and sifter arms  appears to be


Just bare steel - possibly oiled originally to reduce the chance of rusting prior to sale  +1

Looks to be dark finished so phosphate or dark heat treated - both about the sane tone when finished and oiled

Same finish for the band adjusting nuts and rods +1

[Stangly]

Thanks guys for the info, going to try out RPM on the bare metal items, have either of you guys used this product.

[J_Speegle]

Thanks guys for the info, going to try out RPM on the bare metal items, have either of you guys used this product.

Seen it never used it

[ruppstang]

Here is my finished C4.  I sprayed with Boshield when it was finished to protect it.