We covered what SAE viscosity grades mean in an earlier guide — now here's how to actually pick one for your market. Climate is the single biggest factor, because the "W" (cold-start) number determines how the oil behaves at your coldest realistic operating temperature, and the second number determines protection at your hottest.
The general rule
Colder climates need a lower "W" number for easier cold starts and faster oil circulation on ignition. Hotter, more demanding climates can tolerate — and often benefit from — a higher hot-viscosity number for a more durable protective film under sustained heat and load.
Hot, tropical, and desert climates (most of Africa, South/SE Asia, GCC)
20W-40 to 15W-40 is the standard, reliable choice across most of this range for diesel and older petrol engines — this is exactly why it's the recommended grade across most of our country pages for Africa and South/SE Asia. In the hottest, most demanding conditions (Gulf summer, heavy-duty fleets running long hours), a heavier-duty formulation within this range, or a fully synthetic option for premium vehicles, provides an extra margin.
Moderate climates with a real seasonal swing
Markets with genuinely cold winters alongside hot summers need a wider viscosity span — 15W-40 balances both reasonably well for older/diesel-heavy fleets, while 10W-30 suits newer engines built for a broader temperature range and better fuel economy.
Cold climates
Lower "W" numbers become important — 5W-30 or even 0W-20 for modern engines, prioritizing easy cold starts and fast oil flow to critical parts before the engine fully warms up. These grades are far less common across our current launch markets but relevant if you're supplying export markets outside our primary regions.
Two-wheeler-dominant markets (South/SE Asia)
Motorcycle engines run hot and often share oil with a wet clutch — SPL 4-STROKE 20W-40 or 10W-30 with a JASO MA rating (see our ratings guide) is the standard combination across this segment.
When in doubt, ask
If your market spans a wide seasonal range, or you're supplying a mixed fleet of old and new vehicles, the "right" grade often isn't a single obvious answer. Tell us your climate and vehicle mix when you request a quote, and we'll recommend from real, matched products — not a generic default.
Have a specific requirement?
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