tl;dr version:
accidentally bought and used monograde petronas mach 5 SAE 40 in iswara.
what are likely adverse effects of this?

i recently serviced my old iswara (1998). I usually buy my own engine oil coz my mechanic doesnt stock the brand of oil I want.
in the past, i always use magnatec 10W40 for this iswara but my mechanic recently told me its too thin to protect my old engine so he recommended i switch to mineral oil - petronas mach 5 specifically.

so i went and bought a petronas mach 5 engine oil. since this is the first time im buying mach 5, i didnt really check properly what i bought.
turns out, i accidentally bought the monograde version, SAE 40. i only discovered it while i am preparing to buy another canister for my next service.

to be honest, i am quite happy with the oil, the car started fine and the engine runs cooler and smoother with less vibration than before which was a surprise to me. seems like a good move from magnatec to mach 5 monograde EO for an old magma engine.

but i am a bit apprehensive that my engine is not getting the protection it needs during morning starts. is this really a valid concern or is SAE 40 actually perfectly fine to use in Malaysia?

Likely fine. Dont get cold enough here to need multigrade. You want to look at the upper number anyway.

Is fine..my bike using SAE 60 monograde.. nothing happens even went to "cold" places in Malaysia.. still running fine..

thanks for the feedback, guys.

and to further confirm that its fine with technical data, i just found this chart below that shows SAE 40 grade oil actually has lower viscosity at 20 deg C than 10W40 grade oil at 10 deg C.

since the malaysian climate is between 22-32 deg C and 10w40 oil is designed to work in temps as low as -30 deg C, i can safely say that monograde SAE 40 is perfectly fine to use in malaysia.

I'll probably stick to using monograde for my iswara coz its cheaper and works great.



This post has been edited by homicidal85: May 25 2022, 10:23 AM

can use la. no issue.

My spare Car is also Iswara. Yes, old engines need thicker engine oil to protect its internals. Ideally 20w/40 la...thicker so it lubricates and sticks onto each internal part nicely to protect it from wear and tear.

You can get away using the thinner 15w/40 if your engine has been well maintained.

Iswara still road worthy?

Iswara surprises me too. My regular car is a BMW, but I find myself driving the Iswara more often than not LOL! it is the workhorse that taxi drivers in the 90's,00's and 10's love the most thx to its super tahan lasak engine and tough as iron gear box.

Most new Spare parts are so cheap...cheaper than even Kancil and Kelisa! I will never sell my Iswara

4G spare part now no original. Almost OEM that why is cheap.

even those days when the spare parts are original, the prices are still lower than Kancil's and kelisa's original spare parts. I know la..cos my good buddy has a Kancil and Kelisa in his house both used by his 2 younger sisters....and we often talked about cars those days.

I use Shell 20W-50

Buy 20W/50 for older car

where do u stay?? mount kinabalu?? or genting highland??

even if at genting highland should not be a problem. just remember dun "export" your car to country with 4 season.

normally older car, people use higher viscosity is so that is is better to protect the "wear" engine. also reduce possible leakage.

This post has been edited by brkli: May 25 2022, 11:01 AM

sae40 has HIGHER viscosity I.e. more resistance than 10W40 at 10°C.

and yes, if petronas sell it here, u can be sure it suits our local use. basically we don't need multigrade but it is cheaper to sell it than to create a monograde oil series

I want find ori alternator and power steering pump, all no more. Now all from china OEM. And the power steering rack also mcb, claim few pcs already. gg the labor fee.

Ori 4G parts not cheap. Unless you buy counterfeit mitsu product. That one is cheap.

nothing wrong with mineral oil, just need to change nore often.

Same goes for Wira la....but OEM parts are in abundance. It's your luck. Those days even the Original Proton parts also got manufacturing QC problems. what, you think Ori Proton parts those days are perfect is it ?

That API SF rating is the most concern to me. Many cars in the 90's already require minimum API SL rating and newer engine oil.

there is an iswara in my condo block that is well maintained it could put newer cars to shame
if drive nearby no problem la.

This post has been edited by cempedaklife: May 25 2022, 11:11 AM

Those multi-grade are meant for a range of temperature. Many people instead of more common 15W-40, 10W-40 even go for much more expensive 0W-40. The W stands for Winter or cold temp. The lower the number the colder the temp. When it is cold the oil gets thicker. So, the grade 40 oil will become like 50 or higher thus it is heavy to crank the engine and the oil may not flow easily to protect the engine. So, using multi-grade, you can assume that the oil is like grade 15 when cold (when engine start) and to back to behaving like grade 40 once engine reach normal temp.

In Malaysia, we do not have that big temp fluctuation. So, mono-grade is just fine and save you money as well.

wira ... only first batch is best. after 1998 or 2000 almost all rubbish.

Yes, Iswara first batch also the best. After that all lousy too. Why> cos Proton wants to impress the buyers first...and when word goes around that the car is very good then they cut costs by using cheaper parts from second batch onwards.

after making this discovery, i feel like i have been cheated all this while. i live in malaysia. i dont need multigrade bullsh*t that gets thinner faster. i should have been using cheaper, better monograde on all my cars all this while.

I don't even know that there is mono-grade oil out there

Anyway, since my car is service at SC because under warranty then just let it be. The SC will put the full syn because they can make more money

We are hot country, there is no need for W (winter) rating here. Monograde should do fine.

Iswara? Multigrade? LOL
Iswara can use subsidised cooking oil also. RM10 kaotim.

You are right! Many people also didnt know

up

UPDATE: after 3 months using monograde oil, my car takes 2 cranks to start in the morning. I think initially it was perfectly fine because there was still some residual EO (castrol magnatec probably was still sticking to the pistons and cylinders) but over time, the magnatec wore off. So, the monograde oil isnt fluid enough for a one time crank during early morning. But once it starts, it works fine. The engine still runs cooler than when i used multigrade oil.

if your engine is new, I wouldnt recommend using monograde oil just to make sure you have proper protection during the early morning cranks. but for old cars which might burn multigrade EO, its probably a better choice to use monograde because it doesnt suffer from thermal breakdown as quickly as multigrade so there is overall less chance of damage to the engine.

so are you happy using monograde ?

20w40 and 15w40 are actually the same viscosity during normal temperature. Both 40.
I believe your first one might be 20w50 which usually makes the car really sluggish and slow.

later just dump this 4G61 engine into your Iswara

IMO, its the best option for my iswara so I will stick to monograde for this car. multigrade oil tends to degrade quite fast in this car so it is a less reliable choice than monograde. i have googled and there doesnt seem to be any issues with cranking twice. cranking for long periods more than 10 times a day is when you start to see wear on the starter motor, flywheel and carburetor so I dont think my 2 cranks lasting 1 second each time would cause any significant issues.

Actually, multi-grade oil does still matter even in country like Malaysia. The "W" does not only indicate winter usage. A 15W-40 oil is about as thin as SAE 30 oil so it flow better than a SAE 40 oil at normal cold start temperature of around 30c but it stay as thick as SAE 40 oil at engine running temperature.

Most of the time, it won't happen in a short time but long term excessive wear on engine can happen during the first few seconds of engine cold start if the oil is too thick for a fast and smooth pump during cold start. This is especially true for a car that are not start often, for example, once every few days. Oil pump, filter and other key areas has to be taken into account as well. There are reasons when the car manual recommend a 5W-30 oil rather than a 10W-30 oil or SAE 30 oil despite all of it being a SAE 30 grade oil at normal engine running temperature.

This SAE 40 oil, like other monograde oil, are usually only used for older engine model and design or where engine condition are no longer at its optimum level or car that are up and running most of the time such as taxi for cost effectiveness reason.