1 vs. 2 piece axles

[Bad Shrimp]

I need some more edumacation.

Installing rear disks with new Yukon axles on 8 3/4. Disk kit asks for extra shim to be used for 1 piece axle. Whats the difference between 1 and 2 piece axles?

Thanks in advance,

Bad Shrimp

 

[fishy68]

Standard Mopar axles made after 1964 are 1 piece I'm sure. 64 on back they used an axle and hub assy. similar to a front brake hub/drum except it had a keyway cut in the hub to secure the axle to the hub/drum. I assume that's what's considered a 2 piece axle but that's just my best guess.