I was recently asked:

Let me preface this by stating once again that I am not a mechanic or/and engineer. I take my 2001 Xterra off-road and work on it now and then.

My limited understanding is that the “3rd member” in my truck (also called a “drop out carrier” or “removable carrier”) is the carrier that holds the ring/pinion, side bearings, and differential assembly (in my case the locker). It is removable from the axle housing; as such it is a part or “3rd member” of my h233b (housing and axles being 1st and 2nd, I’m not sure what is what).

My 3rd member:


My h233b with the 3rd member out:


In comparison, this is my D44 where the carrier is part of the axle housing:



Hope this helps someone…