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Buy 15W-30 Engine Oil
15W-30 is an intermediate grade that barely appears on cars: cold behaviour as forgiving as a 15W-40, but thinner at operating temperature. You come across it above all in working machinery, stationary engines and a few older specifications.
Which vehicle?
Enter your vehicle - we show only what belongs in it.
How to place this grade
Against 15W-40, the standard in this area: the same cold start, a thinner lubricating film at operating temperature and therefore slightly less internal friction. Against 10W-30: the same film in operation, but more sluggish in frost.
The grade exists where an engine manufacturer specified exactly this combination - usually with fuel consumption in mind under steady load and mild temperatures.
Before you buy
Check where the figure comes from. For agricultural and construction machinery and for stationary engines it is stated in the engine manufacturer's documentation, and then it applies. For a car it is worth a second look: the actual requirement is often 15W-40 or 10W-30, and 15W-30 is hard to source through the European trade.
If your vehicle is listed in the oil finder, you see the approved oils directly - that saves you comparing similar-looking numbers.
Frequently asked questions
Can I use 15W-40 instead of 15W-30?
Often yes, if the manufacturer permits it - the cold start is the same, the lubricating film at operating temperature thicker. If the specification expressly calls for a 30 grade, for fuel consumption reasons for instance, stay with it.
Why is this grade so rare?
Because it sits between two established grades: 15W-40 covers rugged use, 10W-30 the economical side with a better cold start. For most applications one of the two is the more obvious choice.
