yes, try 5w40 one time jan till now. yes use seafoam one time only.

so that's why i say, definitely feel smooth, definitely switch back to 5w30 got effect on this feel.
and i just want to state i FEEL seems smoother than before i switch to 5w40, when still using 5w30.

i dont have any data, just feeling. and sharing what i FEEL. i didnt say seafoam definitely works
i dont mind doing this every 2 years.

and i wont be switching back to 5w40, will stick to 5w30 from now on.
i do have a bottle of 5w40 shell helix ultra left.

responsive, sure better, but most coz 5w40 back to 5w30 lor. cant say much about this and power. like you said, not gonna be very accurate coz of my scenario. i can only record my FEEL

and syukur no leaking after 1 week+ after change. its an 8 years old car.

do check out my blotter spot test: https://forum.lowyat.net/topic/4192241?author=cempedaklife
and check out zeng's comment on it.

This post has been edited by cempedaklife: Sep 4 2019, 04:54 PM

Actually I memang change my engine oil twice yearly. Using fully synthetic. Not so strict la. Sometimes delay a bit cause busy. My idea is even if engine oil still clean and safe to xont use, just change since twice yearly is saving enough. That will also means my engine always run on clean oil. Rather than dirty only change.

Previously last year like that I already clean throttle body. So I didn't do seafoam spray. Maybe next year I will do it. But video show macam need 2 ppl ler. Which is inconvenient for me.

Your schedule on the application looks too frequent for me, but everyone have their own preference. Haha.

Memang nak sell the 5w40. Dunno how jek. Mqybe just post in lyn