I just picked up a 93 NV4500 to replace my SM465. It's pretty clean, no signs of leaks, oil looked like new, and had a rebuild sticker on the PTO cover (I pulled it off in the pics). I drained it, and will be cleaning it up and painting it to get it ready to go in. I'm waiting on my t-case adapter from AA to put my figure 8 NP205 behind it, and I'm going to drill/tap the holes to use my SM465 bell housing. I have 80 miles on my full build of my 57, and already taking it apart to upgrade to the NV4500. This thing shifts through all gears in less movement of the shifter than going through 1 gear on the 465!
I can't locate the GM or Dodge oil, but I can find the Amsoil MTG that specifies it is for NV4500 transmissions. Anyone have and reviews or concerns using the Amsoil, before I buy some?