I have an 04 SL 55. Previously my transmission ECM was replaced because of internal transmission fluid leakage damaging it. Since then, I have noticed that when down shifting in auto mode, the RPMs go up before the "torque converter" grabs. Which is not unusual. However in this case, there is a significant pause (around 2 seconds) between pressing the accelerator and the downshift occuring. However, It is almost instantaneous when using the manual mode. I recently did the AMG challange and did not experience the same shifting problem on the SL55s there. The dealership where I take my car is horrible, but they are the only ones here. So, does anyone have any suggestions on what could be the problem internally with the transmission so I can point them in the right direction. Otherwise, I'm sure that I will as usuall, get the "we can't duplicate it" answer and have to drive around the shop forman for an hour.

how about some help here?

The car got a new master control unit, a valve housing as well as new wiring. All I can say is I can't believe I drove the car for 15k thinking things were OK. The difference is tremendous: Immediate kickdown and shifting. Seems like a totally new beast. If I had not done the AMG challenge I would not have known the difference.

You'd have thought someone would have noticed this at the PDI timepoint. Sad.