Transmission finishing

My transmission has been to the bead blaster. The aluminium bellhousing and the rear aluminium outlet look brand new. The cast metal gear casing has a clean new look to it too. 

There was too much dirt, grime, Arizona sand stuck to it all with the tar thats sprayed on highways. All this was masked by a slow oil leak that ran  the  length of the car front to back.

So now it's been media blasted and looking brand new can someone please tell me if any paint is applied to the cast metal gear casing or the aluminium parts.

Apologies for the long winded question.

Yes I will be posting pictures soon.

When the aluminum casings were made they were wheel abraded to remove flash. That is a machine that throws steel balls against the surface to knock off the flash. When you blast you get fine material everywhere. The aluminum was not painted but had some markings and color daubs. Check restoration info for that. The Cast iron was not finished either. But you can and probably should spray with some of the coatings that are approved by MCA to keep it from rusting. Iron rusts very quickly when clean.

I gave my C6  a light coating with VHT high temperature cast spray # SP998. I thought it matched the aluminum  finish real well and would hold up under the heat and  abuse of being under the car. I was careful not to coat it to heavy to not effect heat dissipation. 

Epoxy primer is the best base for alum. It will stick. Then apply whatever topcoat you want that closely resebles the cast look. Most paints will come off the tranny. They will stick to epoxy primer though

I used VHT high temperature paint "Natural cast grey" after I cleaned my C 4 tranny.

i don't recall the brand paint i used but i know it was "header paint".. they have the lite gray and a clear if u don't want a color. got it at auto zone.

I used Frosts products for the headers. We dont get a wide choice in the UK

I have an FMX so I will speak to the process I used. The markings will be specific to your transmission.  I always encourage getting the grease and grime off to find markings before going the path of media blasting.  On my transmission I painted the bell housing with high temp clear, cast body was painted with Eastwood Cast Blast, and the tail shaft was painted with Eastwood Aluma Blast.  I have 3 years of periodic driving on it now and all of the finishes have held up very well. 

Thanks for the info BK. I may just follow your instruction as it makes sense to try and keep the finish as close as possible to original