turbo 350 problems

[c10ironhead]

Hello, new to the site. I own a 72 c10 shortbed. It has a 350, turbo 350, 9" rearend w/ 350 gears. I had transmission rebuilt about 6 months ago. Everything has been good. I drive 100 miles a day, back and forth to work every day. The other day I was leaving McDonald's and as the truck was gaining speed it was like it hit the brakes. I tried to take off again slowly and it did it again.I shifted to 2nd gear and it still felt like it down shifted hard. I put it in 1st gear and drove it the rest of the way home.
I climbed under the truck the next day and noticed Trans fluid around modulator. The hose was real soft and fluid was in modulator so I replaced it. Tried to drive truck in parking area, and it did it again so I parked it.
My questions are, could it be the governor? Or is it something internal?
Any imputed will be appreciated.