1996 GMC Sierra K2500
Was driving my 1996 GMC K2500 pickup yesterday. In a blink of an eye I felt gear loss, RPMs spiked to redline. Shifting from gear to park im having a grinding noise. Played with my gears a bit when I was safe and found I do get gears when in 4l, 1st and 2nd in 4h and nothing in 2h. Tow truck dropped it off this morning and I started playing a little bit again. I now have gear connection in 2h and the truck will move on its own power when letting off the brake. Grinding is still present going from gear to park. Tranny fluid is good and it was rebuilt 30k miles ago. Im thinking tcase. My ASE certified buddy thinks tcase from what i told him as well as my brother in law. A family friend after playing with it himself is thinking tranny. Anythoughts, ideas or any experiences like this?