2015 ML350 4MATIC W166 leaking problem
Many dealers "overfill" their Service A/B... well documented! Seals can blow for a lot of reasons, but too much oil is the standard! Especially with an almost new vehicle... Verify your oil level!... and definitely right after a service of any kind. If you are unsure of basic maintenance, not confident, whatever... drop by a reputable independent shop(before going back to dealer) and have them document what they have found. This will give you possible leverage should you dealer try to talk out his ***!
my .02
good luck



Can you confirm your car is not a BT engine, but the gas one?