03 z71 tranny problems

[Daniellane]

i was looking at a 03 z71 today.
specs: leather interior,60k miles, 4 inch lift. very niice on the outside. taking care of.

problems: transmission will not go in d or first, but will go once you put it in second and it drives fine after that, shifts good as well. just no go on first and drive. it was driven on a trail by a kid and it was broke when he went into a rut and pressed the gas while the back tire was in the air and it gripped when it hit the ground.

what could be the problem? simple fix? or does it need a new transmission? please help me, im a college kid needing a newer truck