I've already checked the other threads on this subject and done the lifted tire check, but I'm STILL not sure what's going on. Here's what I found:
1) I was specifically told that the car's rearend was a "posi" (I know, not the correct Mopar term, but those are the previous owner's exact words.)
2) Both rear tires off the ground, 727 in "P", tires rotate in opposite directions and the drive shaft rotates. Significant resistance. (This seems like an open rearend to me, right?)
3) 727 in "N", passenger tire rotates, drivers' doesn't (I'm working from the passenger side of the car), driveshaft rotates. (???)
So, I'm confused. The car runs and drives fine so far as I can tell - I've only driven it about 8 miles and not pushed it hard since it still needs a few things to pass inspection and get licensed. The 727 is a standard shift patern manual valve body. Do I have possible tranny problems (wheels rotating while in "P")? Differential problems (only one tire rotates in "N")? Any thoughts are welcome.