Let me correct things here, 5w40 this abbreviation is not as what you've described.
5 - temperature of working condition of that particular oil. *do take note I meant working, not the peak.
That is why there is a difference for some cars that works well in cold start, and some requires a full warm up.
w - Winter - yes correct, and this is because internationally used terms, and there are countries have a real cold weather. It's best if they just use winter as thats the lowest temperature among all 4 seasons.
40 - the grading of viscosity aka in layman's term, thickness.
This affects the performance when the engine oil heats up, whether it expands at the molecular level or so.
And I'm wondering how come Sengasdf never correct this since he is particularly sensitive with engine oils.
Hi boss, how you doing boss? Come sakok boss.
Coolant MAY or MAY NOT decrease in Swift I'm not sure, but definitely it WILL happen in the M16A engines.
By default in all M16A engines, there is a water driven oil cooler.
And how this shit works? Jack up your car, you see 2 small injectors underneath the subframe, which you will not find it in M13A, M15A, neither M18. This is the specialty and the unique design of M16A.
This 2 small injectors sprays the coolant towards your engine, very minor, but at least it does.
Most ppl wit turbo setups will usually have it removed, that is why they will not find the coolant reduce.
But a stock M16A which you keep on redline all the time, will find your coolant/water reduce DRASTICALLY.
Not to worry, it is perfectly normal. Just add back the coolant or water.
But for me, I'm using the water based coolant - peregrine, which you need to mix with 50:50 RO water, I repeat RO WATER ONLY. Don't go buy this coolant and mix with mineral water then come tell me it causes corrosion.
So everytime this water tank decreases, I just add ROs, oh mai Ragnarok Online.
Again, Sengasdf kam sakok. Kthxbai