Personally, I'd take it back and argue that the original repair didn't fix the problem. It sounds like you're having problems 4 months later.. why wait until the car is out of warranty and have it break?

Sounds like their "adjustment" was a first try at fixing it. I am pretty sure they did this to avoid replacing an entire part or assembly.. I think you need to demand the dealer move to replacing "something" since the adjustment obviously didn't work.

If it were my car, I'd drop it off at the dealer and have them look at it again. Get the regional or zone rep involved if the service mgr won't fix it. If they argue, find another W140 on their used lot and make them show you that the other car makes the same noise. If it doesn't, yours is screwed up.

Neal

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