It's aluminum. Mag has to be coated or it corrodes rapidly. I believe that TT uses sand casting for their cases and it's not uncommon to have porous castings when using this method although Japanese QC usually keeps the bad ones from reaching John Q. Public.

You could probably fix it by carefully cleaning the porous area and using something like Devcon 10110 Liquid Aluminum epoxy or the Loctite equivalent or JB weld.

 

There is also a company called alumaweld where you use a propane torch and their aluminum rods to fix it.

 

I was considering Dura Fix. The main reason I was asking about the material is due to having to put a torch right on the metal.

I'll look up Alumaweld. Thanks!

Magnesium doesn't need coated to resist corrosion, though, from what I understand - just galvanic corrosion between dissimilar metals. Transfer case behind an Allison on later model GM trucks are not coated, to my knowledge.

 

aluminum - confirmed by Tuff Torq company

Alumiweld appears to be just about like the Durafix I was looking at.:thanku: