07 Fusion's Transmission shifting hard

From a cold start i can drive in the city or on the highway and everything is great just like when i got it off the lot with 6 miles on it but after about 15 to 20 minutes maybe a little more and then it starts acting up. Like i said it runs great but after it warms up and i hit the gas to speed up or pass someone it will do what i want but when it shifts gears it feels like it holds the gear a little to long and sfifts so hard i get a loud thump and it feels like the motor and transmission are getting thrown out of the car. If i peddle it or lift just before the hard shift i can avoid it for the most part. Background, i have had all the maintenance done at ford on time and years ago took the car Michigan to visit family and the roads trashed all the mounts and i replaced them but its been shifting hard for so long the dog-bone is shot again. Any ideas on why it is shifting so hard? Oh it has never slipped, ever. Thanks