I've had more trouble getting aftermarket filters off than Mercedes brand and upon closer examination I saw the Mercedes filter has a ring of felt or some other soft material where the filter touches the shaft of the holder which helps explain that. The aftermarket ones just have a hard surface there which gets stuck really tight. In any event, you have little choice but to yank away until it comes off...if it breaks then you are in trouble but I have really gone at mine in the past and it hasn't broken (yet).

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz