Additives wearing out?

[Trex101]

I have run M1 SL 5w30 till 4350 miles recently and found my engine emits a noticeable hissing sound when accelerating but when I top-up ½ quart of my engine oil, the sound went away. I been wondering does wearing out of oil additives cause this problem? And does topping up replenish the additives enough to stop the sound?

Btw, my engine oil level before top up is at full mark and after top up is about ½ inch above full.

[ June 27, 2005, 03:32 AM: Message edited by: Trex101 ]

 

[Ugly3]

Doubt that additives have anything to do with it.

 

[Trex101]

I initially suspect oil shearing but from the vast M1 UOA rpt, it seem quite unlikely as M1 5w30 are pretty shear resistant.

 

[Triple_Se7en]

Try a different oil & don't intentionally go beyond the full mark. Your vehicle may not hiss with a different composition synthetic.