While driving home my transmission would not shift out of 1st gear. The clutch seems to operate normally when I come to a stop. Brake master & Clutch reservoirs are full. With motor off shifter seems to go into low or reverse but when started with shifter in that position the truck will stall if I let the clutch pedal all the way up. The shifter when left alone goes to the center of the pattern which should be neutral but when the clutch engages, it is in 1st. There doesn't appear to be any fluid leaks & the truck has 115K.
What do you think?

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