I have 2004 x3 2.5 auto I noticed oil leaking under my car an found that a pipe had poped off . On investigating I found that it WAS transmission oil cooling pipes. i poped it back on and ensured it was secure then topped trans oil back up. However it has happened again. I spoke to bmw they said it could be damaged pipe or what it connects to "HEAT EXCHANGER" together the pipes and heat exchanger cost £200 and then they charge £100 per hour at 6 hours. Anybody experienced this or has any advise plz!!!