9" rear end..?

Hi all,

I’m trying to identify the rear end in my 69 XR7. There is no tag anywhere to be found. I have only a pinion support casting number (C5AW), a Dearborn Foundry marking (DIF), and the attached pic. Door tag and Marti report have the axle as a “6” (3.00 non-locking gears). I suspect it’s original, but would just like to know if there is an easy way to identify it as an 8 or 9 inch diff to satisfy my own curiosity.


gear hump is a dead give away for a 9. thats a 9

Another way is to see if all the nuts are accessible with a socket on an extension. if so it would not be a 9 inch.

It is a 9 inch. You can tell by the hump on the back. Also, unless it was changed, all 69s had 9inch rears.

Thanks everyone…the rookie appreciates your time.


All 1969 - 73 Cougars came originally with a 9" rear axle. It would be very odd to find anything else!

As the others have said it’s a 9" by looking at it. But we all have to start somewhere. Take a look at this guide. One of the best for learning this stuff.