Honestly the rears under the car and painted so I’m not sanding it down it’s not worth it to me for a couple hundred bucks to repaint the rear on my back
Ok...I have some answers.
First though, I didn’t ask nor imply that you should sand your axle. For the most part these numbers on the housing are easily visible unless they were obliterated by aggressive sanding/sandblasting, grinding, or rust.
Why I wanted to know that information was to solve a mystery so to speak. But I did so another way.
As you say your gears are dated ‘68 so I will assume the housing date code is also ‘68 and it would add up that it is due to this:
‘66 & ‘67 model year B body car axles overall tracking width was 11/16” LESS than ‘68-‘69 1/2 model year cars. 58.5” vs 59.2”.
Therefore, each ‘66 & ‘67 axle shaft is ~5/16” LESS than a ‘68-‘69 1/2 axle shaft.
Repeating what I said earlier, you can’t set the original tapered bearing preload if the gap is too much-as in early axles in a later housing.
The bearings walk out of the races and cause excessive play resulting in bearing failure(sound familiar?).
With green bearings the axle gap wouldn’t matter because there is no adjustment on those non-tapered bearings.
I think it’s obvious somewhere along the line somebody slapped earlier axles in your later housing.
Maybe out of ignorance or intentionally knowing they were screwing somebody over. Nevertheless, someone down the line pays the price for it.
Part of the fun of this hobby to me is solving these mysteries and sharing that knowledge with others. All for the betterment of the hobby.
To wrap it up, that axle is from an earlier Dana and won’t work for me or anyone else that has a ‘68-‘69 1/2 model year Dana.