Mines doing the same ... absolutely mad off the line, violent change up from 2nd to 3rd (with significant delay) and then slow to accellerate in top gears. Have been informed that it could be (a) problem with the torque converter, or (b) slipping clutch. Either way it's not good. Let me know what you find out from the diag. I've done a ConZult diag but nothing significant shows up.
Hello Danny
Did you ever resolve this one?.
Cheers