My mother told me that her 1998 c280 began having some shifting issues with the recent cold weather. I have not personally driven it yet, but she says it winds out 1st gear very long way past the shift point before shifting. I've told her to use the manual mode from now on until the car's warmed up. After the car is warmed up it will shift properly. Would a simple tranny fluid flush/replacement and filter change fix this issue. Seems to me the fluid is probably old and could use a changing. Anyone else have this issue?