Attempted to change the oil in both sides today. Engine side went fine. When I attempted to put the transmission oil drain bolt back in, something weird happened. I started just fine and when it was about 2/3 of the way in, it stopped. I took it out and put it back in, same thing happened. I applied a little force and it didn't move. Removed it and the first thread was flattened. It is like it started to cross thread after it was already over half way in. Last oil change went fine and it came out without a problem initially. So, I am going to go pick up a new bolt tomorrow and give it a try. Something tells me that I will encounter the same problem. Any thoughts on what caused this or what I should do about it? The hole is very deep so I don't think I can run a tap through it. Help!