hey quick question, i just bought a 94 ext cab z71 k1500 4x4 with a tbi 350 for a $1000 from a guy i work with, but the trans lost first and overdrive.

how do i identify what transmission it has in it and has anyone ever heard of loosing first and overdrive bolth at the same time? i had an 89 for a while the lost 2nd and overdrive, but ive never heard of one loosing 1st and overdrive at same time.
