I am the owner of a 2002 X5IS with 32,000 miles.
My car has been parked for the last 18months because i have been out of the country. I car is parked in my garage, covered over with a BMW1.35 volt battery trickle charger connected to to the battery. Is there any damage being done to the engine, electrical or body by having it stored like this. what are the long term effects of this storage, should i have drained the oil or at least have it changed.

Thanks fir the advise.
Blue Baby