Judging by the look of the gearbox on the snowblower, the housing was broken when I bought it. I didn't even think to look at that. Good thing it was only 80 bucks and I've already found a used part. I was just a snowblowin' away.

 

So, anyway, the shop finally tore into my tranny yesterday. He said that the support was worn through, and the whole cylinder was burnt for reverse and the forward gears. He was surprised I was able to drive it to the shop. The rebuild will be done Monday and I've learned a valuable lesson re. capabilities of a 4WD truck (as it's my first) and learned how to completely destroy an automatic transmission in a short period of time.

Such is life. At least the warranty covers it, and, if I'm good to it, it'll last me until it's time to trade the truck off.