my first and second shifts were always a little tough before i rebuilt it....after i did and did the 1000 miles break in with atf 3, and switched to MTl, i had no problems....give ATF +3 a try and see how it is, if it shifts smoother then you may have a problem. But how long it takes to become a major issue, is all;based on your driving habits and how worn the parts are.
Lupe
