727 hard shift

Sounds like somebody may have put a shift kit in it and it may not be a great one. I put one in yrs. ago that acted like that. Shifted very hard for a street car. That's why I only use the TransGo kits now because they're consistant. May not be alot you can do short of finding a real good Mopar transmissions man to see if he can modify what's in there or just replace the valve body with a stock one or possibly get a stock one and put in a good TransGo kit in it.