Transmission Shot???

[dmsteele92831]

It's a th400. Ok so last night my tranny feels like it is slipping, I drive it back home and park it. My tranny fluid was a little high and I went to empty some today, but I started the truck first and it wouldn't go into reverse or even neutral. It just stayed in drive. The pointer would be on park and neutral but when gas was applied it would go forward. I flushed about 7 quarts of fluid through while pumping the old fluid out (it was reddish-black). After that I'm still having the same problem, I'm guessing it's time to go shopping for a new tranny? Also should I stick with the Turbo 400? I have 3.07 gears.