Hi,
i'm driving WAJA

i have some questions in choosing the right "oil" for my car
last time i was using castrol gtx, but then ppl recomment me the roadster because of the cheaper price (means price of 1 roadster < 2 castrol)

is that true that SM is better than SL??

CASTROL GTX SM/CF (5000km)
15W~40

ROADSTER API SL/CF (10000km)
SAE 15W~50

i'm noob about car thingy anyone can tell me? thx~

IIRC, SM is the latest standard. theoratically, its better to get the highest standard available, but most reputable engine oils are made to exceed SL standards, which could also exceed SM standards, so the difference shouldnt be much.

but that is comparing between standards of the same brand. it isnt a good gauge to compare between brands.

Can we mix the new engine oil if we still have the old ones inside the engine?

u mean top-up with the same brand or wat??? if u wanna top up its no problem. just make sure u still do ur service at the recommended oil change interval.

bro, try search for Q8 engine oil. most of car's monster using that one. hehe

Yup API SM is the latest standard. Petronas Oil exceeds API SM level

if its from the same type shouldn't be a problem
If you're changing from mineral to synthetic, u need an engine flush