front axle shafts

[chuckster]

O.K. guys....first post here. Been peeping on the site for a year or so now. I have a really good question for the DIY folks. First a little background on myself and my X. Bought a 2000 4.4 18 months ago. Really love the vehicle although I have had my share of problems. Got it dirt cheap...at least I think I did....from a friend who had to make a choice between his wife's X or her Escalade. He decided to hold onto the new Escalade and sell me the BMW.
Now my question. Went to replace the front axles today and ran into a bit of a problem. New axles were purchased from Rock Auto which I saw someone post about purchasing some parts from on an earlier post. Chose to start with the passenger side or right side to begin with. Fairly easy procedure with having read several posts on here before. Took about 45 minutes. Drivers side / left side was a different story.
Almost finished the job when I noticed the axle nut did not pull the axle out through the rotor as far as it did on the right side axle. Found that the axle, just beyond the splines was too large to fit into the rotor and seat properly. Had the rotor locked down, would not turn. Went to 2 local parts stores that actually had the axle in stock and they were the same as the new axle from Rock Auto. Had to re-install the old axle until I can figure out what kind of beast I am dealing with.
I put a micrometer on the area that goes in the rotor assembly and on the old axle it measures 2.33 in. and on the new axles the same area measured 2.55 in.
Any help/suggestions/advise/or offers would be greatly appreciated.
Also, no disrespect to Rock Auto. Their service is great and very timely. I think I just happen to have something unusual, maybe.
Thanks for any help!
Chuck