Where are the casting #'s located on my rear end?

[Jacob A.]

Hello, I am trying to I.D. the rear end in my Corvette. It is a 67. I see one raised set of numbers that appear to be a date, like you would find on an engine. I believe it says H266 Is that August 2nd, of 66 of August 26 of 66? If so, that makes sense. My car rolled off the line Nov 14th. 66. Other than that I see an upside down GM and directly above that there is a raised number, it is upside down too, like the G.M. one is. Where else should I be looking. Should I find an AZ somewhere on the axle or on the differential to designate the 3:55 435 4spd?

thanks in advance.

Pictures would be great!!!!

Very Best,
Jacob

[John H.]

Re: Where are the casting #'s located on my rear end?

Jacob -

The ratio code and differential assembly date are stamped on the as-cast surface on the bottom flange of the housing, between the camber strut rod bracket and the spring retainer plate - will take some cleaning to see them.

The casting number (3899143) is located just above the horizontal "fin" on the passenger side of the housing.

[Wayne M.]

Re: Where are the casting #'s located on my rear end?

Hello, I am trying to I.D. the rear end in my Corvette. It is a 67. I see one raised set of numbers that appear to be a date, like you would find on an engine. I believe it says H266 Is that August 2nd, of 66 of August 26 of 66? If so, that makes sense. My car rolled off the line Nov 14th. 66. Other than that I see an upside down GM and directly above that there is a raised number, it is upside down too, like the G.M. one is. Where else should I be looking. Should I find an AZ somewhere on the axle or on the differential to designate the 3:55 435 4spd?

thanks in advance.

Pictures would be great!!!!

Very Best,
Jacob

Here's a few pics; castings and stampings -- some from a '67 "AU" = 3.36 posi. 2nd pic is stamping on top flange (near rear cover). 3rd pic is of an early '65 carrier; you can see the casting clock -- your date cast is on the opposite side, as you've found. The GM and "1" is the mold number. Your cast # near the nose will be different for '66 & '67 (IIRC, it ends in ...143).
.

[Jacob A.]

Re: Where are the casting #'s located on my rear end?

Hello,

Thanks a bunch John & Wayne, I certainly appreciate it. I will do some cleaning and re-post what I find.

Very Best,
Jacob

[Jacob A.]

Re: Where are the casting #'s located on my rear end?

I guess this is going to take a little more elbow grease than I imagined. I have been down under the car with a small wire brush. I have hit the areas in the pics... I still don't see any stampings yet.

Feel pretty confident it is the original rear-end. I have complete documentation on the Corvette, and none of the other 4 owners ever spoke about replacing the rear axle.

The car was sprayed with an "undercoating" before it was originally delivered to it's first owner...(at a cost of $30) I think this undercoating is still flaking off the diff!

Any suggestions on what to use to clean the metal a little better? (other than a steel brush) Will the steel brush rub through the stamping?

thanks,
Jacob

[John H.]

Re: Where are the casting #'s located on my rear end?

The car was sprayed with an "undercoating" before it was originally delivered to it's first owner...(at a cost of $30) I think this undercoating is still flaking off the diff!

Any suggestions on what to use to clean the metal a little better? (other than a steel brush) Will the steel brush rub through the stamping?

thanks,
Jacob

Jacob -

Try mineral spirits (and a brass brush, not steel) first, then carb cleaner.