When the car is cold it works fine.As soon as it warms up the problems start. The engine light comes on the code is p10715 . the car will shift into 1-2 fine but 3-4 will not engage the car revs high and thats it. so i replaced the mainshaft speed sensor and the countershaft speed sensor. I have not flush the tranny fluid. The car work fine for a little while but started up again any suggestions will help.the car has 170000 miles on it. i did do a tranny service two years ago.