Here's what's going on with my 300e trans recently: in the cold canadian mornings the trans takes 15 seconds to engage in drive / rev. then itstruggles to get going, but eventually it starts moving ok..but until the thing is fully warmed the shifts (esp. 2 to 3) are hesitant, bucking somewhat as though undecided wether it wants to be in 2nd or 3rd....when it's finally at normal temp...it's pretty much normal.

To make it worse the other day at full hwy speed the the trans sfifted down from D into 3, on it's own...I had stop, check / add ATF and after this, all was well(ish) after that...I have seen no evidence of leaks under the car. What is failing in this thing?

HELP!