A method is provided for calibrating an automatic transmission with a torque converter clutch. In order to avoid that the torque converter clutch still has capacity even if the pressure is commanded to be zero without modifying the behavior of the torque converter clutch behavior of all the production, the torque converter clutch minimum offset transmissions are detected and only on these transmissions the torque converter minimum clamp pressure is decreased by a pressure step and the torque converter clutch coast adapt reference cell is increased.