Well, since you know they didn't use the OEM seals, for whatever reason, that is where I would suspect the problem to be first and foremost.

I don't know if the audi seals are "interchangeable" or not but I can't understand why they would not just use OEM parts. I ordered a set of seals for a 34 year old 240D from my dealer and they got them in 2 days and for $20...how could parts for the OM606 be "unavailable"??? I'd tell whoever made the executive decision to proceed with the incorrect parts to redo it right.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz