First and foremost.. Forgive me if this is a stupid question.

But I found 2 old engine oil "tong" in my store..
1 of it says: "Exceeds API SL" . The other 1 says: "API SM".
Both are same SAE 5w-30 grade.

Are they the same grade/type of engine oil?
Because I plan to mix them together and use for next time engine oil change.. Save some money.

Please let me know if I'm making a big mistake mixing them together.

It's like these 2 engine oils. One is 'Exceeds API SL' , the other is 'API SM':

that is like choosing between GOD car or newer 'god' car...
both a great car but you cant compare due to different era...
the era of GOD car is the previous dugong...

SM is newer...
during SL there are no SM, yet, thus the phrase exceeds SL rating....
you just dont know how far it exceeds...
you just can be sure that SM pass the newer rating...a better and safer choice...

for perodua engine oil, currently they still selling the "exceeds API SL" and API SM even in today's new packaging, refer this link url:
http://www.wemotor.com/blog/2014/05/perodu...ricant-bottles/

I guess there must be some difference either is base oil, or additive package.

This post has been edited by voscar: Mar 28 2015, 11:39 AM