Axle ID help needed

[cboss70]

Hello Everyone,
A few years back I bought a pair of 31 spline for 9" axles so I could use them in a 70Boss I had but ended up finding the originals buried in my garage. Every once in awhile I think about using them in a 67/68 9" housing I have and using it in a regular GT mustang.  The question I have is are the 31 spline axles different between 67 and 70 shelbys and mustangs that came with 9' and 31 spline from the factory and if so are the differences visual (marks or tweaks in look? what are they?) or functional (ie these wont fit say in a 67 or 68 Shelby GT500 housing w/3rd member).  I always thought they would work in any 67-70 9" housing with a 31 spline center section but can't remember for sure. Just hoping for a little education before I try to use them in a project or get rid of them.

[Bob Gaines]

Hello Everyone,
A few years back I bought a pair of 31 spline for 9" axles so I could use them in a 70Boss I had but ended up finding the originals buried in my garage. Every once in awhile I think about using them in a 67/68 9" housing I have and using it in a regular GT mustang.  The question I have is are the 31 spline axles different between 67 and 70 shelbys and mustangs that came with 9' and 31 spline from the factory and if so are the differences visual (marks or tweaks in look? what are they?) or functional (ie these wont fit say in a 67 or 68 Shelby GT500 housing w/3rd member).  I always thought they would work in any 67-70 9" housing with a 31 spline center section but can't remember for sure. Just hoping for a little education before I try to use them in a project or get rid of them.

The short answer is that you can use them 67-70 Mustang 9in housing without a problem.

[gt350hr]

     One more thing to add to Bob's reply. Your axles do not have the "sleeve" that the factory used on '67-70 axles , SO you will have to use the "regular" 28 splice axle seal and "carefully" slide the axle in through it so the seal surface isn't damaged. 31 spline axles made before '67 ( Galaxie , Thunderbolt , A/FX Mustangs , and '66 427 Fairlanes ) did not have the sleeve . In '67 Ford's "better idea" was to use the sleeve and make a new larger seal ( C7OZ). The sleeves are available now and you could add them and use the large seal if you want.
     You ended getting more than you asked for.
         Randy

[cboss70]

No, thanks for the added info that's great.  The axles did have the sleeves and I cut them off when I removed the old bearings and used the retainers that came with the bearings because I read on this form that you could just use the 28spline seals. I guess that was probably not what I should have done but at least its an easy change.   So is sleeve vs no sleeve a distinguishing feature of what year the axles are from? I'm still curious what year mine could have come from the factory in. 

[Bob Gaines]

No, thanks for the added info that's great.  The axles did have the sleeves and I cut them off when I removed the old bearings and used the retainers that came with the bearings because I read on this form that you could just use the 28spline seals. I guess that was probably not what I should have done but at least its an easy change.   So is sleeve vs no sleeve a distinguishing feature of what year the axles are from? I'm still curious what year mine could have come from the factory in.

If you re read reply #2 Randy's description suggest it does. There are other tells like the face of the hub and the machined contour of the back side of the hub. The face of the hub has a lot of crud still on it so hard to say definitively and no pictures of the back side of the hub (between the backside and the bearing). Given you indicated you cut off the sleeve would indicate it is a later variety. If planning to resale then there is not much difference in value given they are covered and the details nuance. 

[gt350hr]

  +1 and "sometimes" you can see a "year" in the end of the axle, other times the drilled holes take them away. For example , the 31 spline axles ( A/FX Mustang from '65) have C5AW on the end , and My 68.5 CJs say C7OW. One other pair I have aren't readable and one last set says DOOW on the end. Those are "forging" numbers and only tell when that forging was created. A revision would change the forging number. Not for a machining change but for something to alter the forging itself.
    Randy