1988 suburban, turbo400 trans (3 spd.) automatic. . . . .when shifting between 1st and second gear, it literally jumps, real rough, no grinding but i would call it a jump. this occurs when i am real easy on the throttle or real heavy on it. when i am punching it it will "chirp" (tires) . . . .it is hard to find the middle ground where it is a seamless transition....what do you think?