i had a motor installed and i believe the mechanic may have not filled the trans fluid properly to full. from a dead stop it clunks into gear after getting to almost 1000rpm before it goes forward occassionally. then it downshifts every once in a while too soon. it almost feels like it didnt know what gear it should be in when slowing down. now after all this in the moring when the car is cold it is fine no problems, once it reaches operating temperature it shutters and then gets stuck in high gear and the gear light comes on. not sure what this is or if filling the fluid only will fix this problem. heeeeeeeelp!