1994 Isuzu Trooper

Transmission problem
1994 Isuzu Trooper 6 cyl Four Wheel Drive Automatic

when transmission changs out it go, s out of gair, it has all the gairs untill it shifs out. And then it want pull at all only thing lift is low gair and revrus, when it would chang into high giar it would chang out hard thats the only wanning we had and did not do that every time can you help me ps. Steve