If your car requires a 15W-40 engine oil, Castrol offers a full range of options to meet the needs of every driver and vehicle manufacturer.
15W-40 viscosity grade means it flows like a 15 weight oil from start up in Winter, but provides the protection of a 40 weight once the engine reaches full operating temperature. If you need a 15W-40 diesel oil, Castrol GTX helps extend engine life, protecting against the wear and tear of severe weather, rough roads and heavy tows.
There are two things you need to know to find the right oil for your vehicle 1) the viscosity, 2) the manufacture specification requirements. The products on this page are all 15W-40 viscosity and also show the manufacturer specifications details.
To find the product you need always consult your vehicle handbook or use our Oil Finder tool.