[Chuck78]

A quick search answered part of the axle spline count question, apparently all 60-68 GMC Dana 44 axles are 30-spline. That makes things a little bit easier now if carrier bearings will be able to be sourced to mate the newer Detroit TrueTrac or Nitro Helix carriers into the older GMC housings...

https://6066gmcclub.com/showthread.p...=Dana+44+axles

Originally Posted by summersmoker

The parts manual helps narrow it down. I'm pretty sure the right part # is 2402517 (which according to the gmpartswiki.com became # 02494739).

and:

Originally Posted by Charon

1960-68 gmc dana 44 same axles. Not really to hard to find. 61-74 international 1/2 ton works but the flange needs redrilled for 6 bolt pattern and the center hub turned down.

http://tinyurl.com/jptmkjy

Dana-44_1967-1978.pdf which that links takes you to is a Spicer catalog. Page 133 is 1967 plus GMC Dana 44, page 177 is international harvester Dana 44 half ton axles. It shows the part numbers for the GMC axle shafts no longer available, does not give a part number, only in la. But the international axles, it shows part numbers for all of them. They do show a different left versus right shaft however. What I had read here says that the GMC uses the same shaft left and right? I'll have to see if I can find any reproductions to verify that.
The half ton International Dana 44 axles are probably a 5-lug I'm guessing? That would be a bonus for me if any of those were the correct lengths for the '60-'68 GMC. I could run off the shelf International Dana 44 axles and off the shelf 1987 pickup or 1991 Suburban front rotors and have my current 5 lug setup.

That link does have part numbers for the carrier bearings as well, so I can at least look that up at a later date when I get more serious about this, and see what the sizes of those bearings are versus the Detroit TrueTrac OR Nitro Helix 30 spline Dana 44 limited slip.