Hello guys,

07 XF manual.. 100k miles..

So I've went to muffler delete an wk ago, starting to notice there's like diesel truck like noise when im IN GEAR + LOW RPM. When its parked or in neutral, I can't hear it even if I rev. Only hear when its in gear and when car is moving. It quiets down once rpm goes over 2.5k or 3k.

I saw couple of threads saying m112 engine has some particular noise and was wondering if it sounds familiar with other XF owners. First time with this engine, got myself too used to jdms lol

It sounds like.. GLLLLLLLL, like.. Gargling? Truck idling? Tried to take video but can't really catch the sound on vid.. I've changed oil to mobile1 European something* 0w-40 about a month ago and maybe its too thin and can make sound?
tried to find similar sounds on YouTube for days, this comes closest I believe.

https://youtu.be/ysVdJtT6bPU

Sound is more noticeable when engine is on heavier load, like starting to move with 2nd gear from light. Doesn't make any change if cars cold or warmed up. I think it's not the exhaust sound, as I can hear both growling and gargling at the same time but still very distinctive.

Hope I explained clear, will take any advice!
Thinking about Liqui Moly Hydraulic Oil Additive if it can help? Never used it before but reviews were good..?

Thanks!

 

Muffler deleted and it sounds different immediately after? Hmmm, let me think about that.

 

Its probably me noticing more. Because this noise was there for low rpm all the time but very subtle, definitely got significantly louder enough to get me annoyed after muffler delete. Also is why I am worried, as if it was some kind of tranny wear, it shouldn't get louder by deleting muffler. Planning Liqui Molly tomorrow n see if theres any improvement at all.