Would "non API certified" oils void the vehicle's warranty?

Viscosity does not translate into protection. Film strength provides the protection from shearing but there is no film strength indicator. Viscosity just means the fluids resistances to flow which is another meaning for being thick or thin. A lower viscosity number does not always mean lower protection.

i would say older api are means for better performance,newer api are better for environment,coz they reduce amount of additive to meet for emmision standard.correct me if i'm wrong

I use Premium Mineral 5W 30 for 5 years, switch to 10W 40 SL Nxxx brand because of Engine keep reducing. Maybe the oil too thin... Just switch to 10W 40 SL feel that the car power reducing, maybe that's the meaning of you, Viscosity change from thinner to thicker, but is from Mineral to SEMI.... After that switch to Magna Brand 10W 40 SM grade, the power is coming back, even compare to 5W30, it is better.... I will going to try this Magna Brand SN Grade next service... Will giving the general feedback regarding that...

I choose this brand is because it is the cheapest compare to I use before and also I saw in the market, SEMI 10W40 SN/GF5. You won't get such grade in only RM 90 in the market... Except those fake oil or fake bottle.

Nasa got Mineral Oil in 5W30... I use it because it is cheap and it is worth for my car, I service it once a month as it reach 5K KM already.

SN is not always better than SM, fully synthetic is not always better then semi synthetic. I have customers boasing on using shell's helix ultra, mobil1, and whatever fully synth oil in the market. I sold them another oil at half of the price they paid for their previous oil and it performed much better.
Btw, I don't care wether it's an SL or SM or SN. As long as it produces results, and doesn't degrade over time.
Guys, do you all feel your car having the brand new fresh feeling everytime after an oil change?

I always use this info when choosing my engine oil. There are more than these in oil technical datasheet and it means alot for those who understand ..

find your car owners manual, and check the recommended oil. there they would have stated the minimun api rating to be used for the car.

izit because of it's HTHS?

Using cheap oil without understanding your engine requirement is dangerous. Understanding oil and your engine safe you money and trouble. TBN is mention in the datasheet, but again need to check the TAN no of the oil..Eg No point having a oil with TBN of 9 but TAN of 4. The oil cannot last long too.. Doing VOA and UOA is the best way out..

I thought we only need to look at the number behind the "w" ?
In my observation, most 10w30 oils are mineral based, while 5w30 are mostly semi syn.

and proton uses xw50. LOL

COE themselves. Word from my BLM customers' mouth

This is one of the very strange things that I personally have no clue until recently.. My friends driving exora bold , in the manual stated 10w-30, but went to Proton SC , they use 10w-40..

For a sincere question, you want your car last longer or just a few years? Actually if your car got engine oil, no matter you change it or not, your car still can move, just the life of the car engine can last longer or short. If you like to REV, choose higher Viscosity engine oil is help to protect your engine, lower viscosity is for economic use because it is thin and light, your engine can run very easier compare to higher viscosity engine oil.

I argued this with two sc, they said , cannot be 10/30 all campro based engines ,they pour 10/40. When i showed them d book, they kept quiet. So, i didnt go back to them....
I finally found one authorized center, that, the moment thry saw my car, they said...this cfe engine, and cps , must use 10/30. If not long run problem. Dah dua kali service dah, pakai 10/30, 10k oci. Car runs well, though starting 12th, might need to slow down....cant risk the summons by d new system already...

That film-forming feature only available in semisyn & above ?
How great if Mineral also got MoS2...

Actually everything is based on their spending power... They use better oil to protect their engine are their choice... Same thing that you wearing branded clothes and normal chothes... Better quality is giving better protection, This is always customer thinking...

Use Synthetic for Diesel engine is ok too, problem is that's too much expensive compare to Petrol Engine, since they use more oil compare to diesel engine... If you use the transport for working, you need to service more compare to others, you will think about cheaper and also quality oil to protect your engine...

I already found out mine, how about you?

if you have certain conditions (eg: skin diseases), id think that you may need distilled water or well treated/filtered water.

likewise, if you're driving is all about getting from point a to point b, sure. why bother anything over mineral right?

however if you'd like to have a bit of fun in your driving, go high revving, heavy start stops etc (if you're driving fast in traffic, you're ought to face harder braking situations and high revving again to pick up the pace)

i'm sure if you're a car person, you'd like to have:
1) more protection to your engine due to your behavior
2) having engine oil that provides less friction/coating to your engine so that it performs/revs better.

now, i have used almost all the mainstream mineral oil (shell, caltax, mobil, petronas etc) before i moved to semi syn i am using now, i can tell you straight up that none of them can last more then 2-3k km without my engine feeling sluggish, and none of them can provide me the smoothness and/or faster revving that i am having now.

granted, this is more of a "user problem" than an engine or engine oil problem. however its their driving, their money. who are you to judge?

shell? tried mineral and for once semi syn.

i just want to say that my engine feels damn refreshed after an oil change from either of those oil at 5k km (the semi syn at 7.5k because thats what all the "sifus" said [5k min/7.5k semi/10k full] lol).