I just did an oil change this past weekend on my 2006 E55 with 45k miles, and ever since then I started hearing this high pitched whine from the engine. Not sure they are related or purely coinicidence. The noise is especially pronounced when moving from a stop or at low speeds, I can't hear it at higher speeds but that could be just because the road noises drowned it out.

Any ideas what may be causing it? Should I be concerned and take it to a dealer? The car is bone stock.

it happened to me also the first time a did a oil change when i bought my car. it eventually goes away

hmm... wierd. I will just wait it out for a few days then. Thanks.

https://mbworld.org/forums/w211-amg/...oil-today.html here is my thread on this exact thing. also check ur PS fluid level. i topped mine off and now when engine is warm it dosent whine to much

Thanks for the link, looks like quite a few people had the same experience. The noise is still there after more than a week and doesn't matter whether the car is warmed up or not. The car seem to run just fine though.

That's the scary part. Wasn't there before the oil change (last week), and now it's there all the time, with no observable difference in normal driving.