I got the differential out of the car and the new one ready to go in. I wanted to know what the proper finish is. Mine was painted black, but not sure what is correct. I was going to wire brush the new one but not sure what to paint it if at all. Thanks,

Bill

 

As you may or may not know, these early rearend center sections had various color splashes, daubs, stripes, etc painted on them at what seems to have been sorta kinda random patterns. I have asked, and asked and asked about what the various colors and locations of these painted colors represented. None, I mean ZERO of the "experts" have provided information about what they mean. Also, these various paint markings have always APPEARED to have been applied BEFORE the final surface paint was applied. Also, as has been determined, the completed rearend assemblies were supplied to the assembly plants (such as St. Louis) with minimal paint (generally black) and AFTER the chassis was assembled, then the entire chassis was painted with what is generally termed as chassis black. Thus, BEFORE body drop, everything excpet engine and tranny were covered with black----------------including the rearend and any paint markings that had previously been applied at the Detroit Gear and Axle plant (Corvettes ONLY got rears from the Detroit plant, NONE from the Buffalo plant).
Now, with all of that said, when I rebuild a rearend for a customer, it gets painted with a satin black on the exterior, UNLESS it is a 56-early 57 rear. The 56 and early 57 center cases (as best as can be determined) were painted (both in and out) with some sort of a red oxide paint.

Here are some of the paint markings I've seen on rears. As can be seen, it APPEARS that black was originally painted on some. I've noticed that black is more predominant on the later rears.








This is the original red oxide finish on an early 57 virgin rear that I recently rebuilt.




This is the inside of a later (about 61) rear after I washed it in the parts washer. As can be seen, NO paint inside, only the paint marking for the pinion shim.


This is the outside, after washing. As can be seen, black appears to have been factory applied.


This is the same rear after I finished.


That's how I finish a rebuilt rear---------------UNLESS the customer specifies otherwise.

Tom Parsons

 

Thanks Tom. Very interesting and informative answer, like always. I am going to go back and look closer at both rear ends for any of these markings.

Bill