Interesting one this. Had my 2015 Seat Leon X-perience 2.0 184 DSG in for service today at Seat. I wanted the Haldex servicing as it’s a fairly rare model with the four wheel drive.
I went to collect it to be told the Haldex is a sealed unit and whilst there’s a drain plug they said there wasn’t a fill plug.
I challenged this but got nowhere. On coming home had a look under the rear and found what I believe to be the drain and fill plug. Sent the photos off via email to an embarrassed service chap and now waiting contact.
I’d welcome thoughts.