But then the other Friday I went on a pretty long trip and put a few hundred miles on the truck, then parked it out front for the night. When I went to move it back into its normal spot Saturday morning, it would only go into R. No forward gears at all, no matter how long or high I revved it. A quick Google search told me I was most likely going to be rebuilding it, but I ordered a filter and gasket anyway because I found one for less than $10 shipped.
Well, this weekend I got a break in the crappy New England weather and some time so I decided to take advantage of it and drop the pan.
This is where it got interesting. 13 of the 17 bolts were either loose enough to remove with my bare hand
, or just needed me to slip the socket over them without needing the ratchet. 
3 forward bolts and 1 rear bolt were all that were more than hand tight. This was all the more surprising because there were no leaks around the pan (the transmission doesn't seem to leak at all, it's never been low on fluid, but I do occasionally find red oil drips here and there, just never from the pan). Any way, dropping the pan was easy, but the fluid came out way too clean for my liking. I was convinced the filter and gasket weren't going to do anything since it was obvious the filter wasn't clogged, and the fluid was not burnt or contaminated. I even considered changing plans right there and taking the entire transmission out, but thought if it came to that it'd have to wait so I went ahead and swapped out the filter and cleaned the "silt" out of the bottom of the pan. There were some metal bits in the filter (I know the transmission is not going to last much longer, but I'm going to eek as much life out of it as I can until the budget opens up a little for a rebuild), but it was otherwise spotless. On the bright side, the cork gasket was actually fantastic because the bolt holes were ever-so-slightly smaller than the bolts so I could stick them all in the pan and the gasket held them and they held the gasket in place making getting the pan back on a breeze. Then I went around the pan a few times snugging each bolt a little more with each pass until they were all tight without being too tight. So far no leaks.
The best news, maybe it was the silt in the bottom of the pan blocking the filter hole, or maybe I knocked something loose that had gotten stuck, but whatever I did it goes into gear again with only ~$40 worth of filter and fluid instead of having to have it rebuilt (yet).
