Reason for oil change: I've had the car 3 months and don't really trust the originating dealer to have done (the appraent full service) correctly. My Timing chain is making noise which according to the 5 mechanics who have listened to it (including a indipendant BMW specialist and BMW themselves) is quite normal. No, its not "normal" its actually a little intrusive once hot. (No noise from cold btw)
"Why get a car with a noisy chain?2 I hear you say, well its a long story but the answer is: "I fu*ked up"
So, i have to deal with it.
Now, "Fix the chain" will be the next thing you say and normally i'm with you......except its an engine out job and i aint got €2k to spunk on that right now. I'm going to have to work with it as it is. However, there is no Clicking or ticking, its just friction noise of the chain on the guides, According to the internet (uhoh) this isn't unexpected and i can't get a mechanic to tell me its bad so i am where i am. One interesting thing, My dealer told me that the oil he got from BMW for its pre-delivery service "was like pi$$" and i have come across that comment regarding same before, which makes me thing (stay with me here) that perhaps upping the Viscocity of the oil from (afaikt) a figure of 9.8 cSt (5w30) to something a bit higher, perhaps a robust 40. I know some of you are reading this going "oh my god change he chain ffs" but i can't just yet
So, i've been researching the cSt's of oil, looking to see if i can use something different to help me. As far as i know, the tensioner is spring, not oil pressure based so having a low 30's oil to boost pressure (and the chain tension) isn't an issue. Also, i know you can say that if its working fine and mechanics are not worried, "Whats your problem?" well, noise is energy and if my chain is making energy, its doing so in a way which may speed upp wear ( its rattling/scaping on a very thin oil film)
So here we go, read and laugh....