Great advice from both of those fella's, but also remember to recheck your tranny fluid. If something that drastic happens, right after changing the fluid, most likely it is from the fluid level being too low. So double check that.
If you can verify that your fluid level is good, when hot, then I agree that you need to start looking into at least a valve body and the other items listed by Tony.
Also, if you do change out your valve body at any point and time, check out
www.axiom.com . They have really good prices on rebuilt vavle bodys that are rock solid. Quite a few around here have purchused one from them, Lord knows I will when and if I have to rebuild my tranny again.
Best of luck and welcome aboard!
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