Differential Size

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Good Day all! I have a 1965 mustang, 289 all stock. I need to replace rear axel seals, bearings etc. Is there a quick look method of knowing what size (8 inch ?) Differential I have.
I appreciate your time and answers.
I believe the easiest way to tell an 8 from a 9 is by trying to fit a socket on the bottom case nuts. If you can get a socket on all of them it's an 8". If you can't get a socket on 1 or 2 of them on the bottom it's a 9. There may be an easier way but that's the way I am aware of.
 
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Does it have the stock rear end?
Stock 1965 stangs use same wheel bearing for the 8 or 9 housings.( 9 inch being a tampered tube housing)
But being an old car rear end could of been swapped out, then you need to now the axle housing end bolt pattern

Pics of both sides (front and back) for a better answer please.


Part of me wonders if your asking for a way to determine gear ratio
Either way welcome aboard Lake Martin John and post a pic of your cool white coupe!
 
Does it have the stock rear end?
Stock 1965 stangs use same wheel bearing for the 8 or 9 housings.( 9 inch being a tampered tube housing)
But being an old car rear end could of been swapped out, then you need to now the axle housing end bolt pattern

Pics of both sides (front and back) for a better answer please.


Part of me wonders if your asking for a way to determine gear ratio
Either way welcome aboard Lake Martin John and post a pic of your cool white coupe!
Much thanks gentlemen! I'll get under it and take some pictures as well as giving it the socket test........
 
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