[QUOTE=aaronng]Interesting. I just went from 0w-40 to 10w-30 as well and I observed the same thing. Louder engine noise (tapping) with the 10w-30. But it is smoother now with 10w-30.
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Are u still using Castrol or changed to another brand in the 10W-30 grade?
Why or how do u describe (?? ) the 10W-30 being smoother than 0W-40 in the Euro Accord? I am about to try 0W-40 so some feedback would be good!


With the Mobil 1 10W-30 and tapping noise problem, I'm not sure if its because it doesn't produce enough of a protective film or something? But my idea shouldn't make sense either, because Mobil 1 is suppose to be very protective for moving parts and oil analysis shows this to be the case too. So really have no idea. But in certain cars like I said, the Mobil oil gets CONSUMED easily..



As for other person - why do u insist on using 10W-40 (even from 10W-50)? Honda's are suppose to have many internal engine parts and also having revvy engines, and as such u should use the recommended oil range. In fact, it is probably safer to go 'thinner at normal operating temperature oils' such as 5W-30 or 0W-40 as it protects the engine parts when its revving/moving fast. Also gets more power.

People always recommend Honda's not to use too thick an oil. It makes sense scientifically to me (although I haven't verified its truth). BUT.... without having a way to verify either way, the oil grade that the manufacturer recommends and the dealer uses is probably the best - 10W-30. Even if you go on the track... Just change it afterwards.