Transmission broke????

[98Longbed]

I have a 1998 3.0 v6 Ranger with 113000 miles. This afternoon while driving down the road I heard a clunk sound and then my truck lost power to the tires. Engine did not die. So here's what I know, truck will drive in R, 1 and 2 but while in 1 or 2 it doesn't feel right. When put in D it will move forward super, super slowly and almost not at all. Mechanic I know mentioned valve body to me and suggested I take it to transmission shop. What can you guys tell me? Help, advice, suggestions are appreciated. Thanks.

 

[SMTGREG]

Remove the trans pan for inspection and look for metal. I suspect a failed forward planetary gear or drum. If there is lots of metal replace trans and flush trans cooler.